Thermoplastic elastomer composition and molded article

ABSTRACT

The present invention provides an acrylic block copolymer composition improving melt flowability at molding and being excellent in heat resistance in addition to keep weather resistance, chemical resistance, adhesion property, flexibility and abrasion resistance which are the characteristics of the acrylic block copolymer. It is attained by a thermoplastic elastomer composition comprising an acrylic block copolymer (A) which comprises a methacrylic polymer block (a) and an acrylic polymer block (b), wherein at least one of polymer blocks among the methacrylic polymer block (a) and the acrylic polymer block (b) has an acid anhydride group and/or a carboxyl group, and an acrylic polymer (B) having 1.1 or more of epoxy groups in one molecule.

This application is a national stage of PCT applicationPCT/JP2005/000823 filed on Jan. 24, 2005, claiming priority based onJapanese Application No. 2004-023865 filed on Jan. 30, 2004, thecontents of which are incorporated herein by reference in theirentirety.

TECHNICAL FIELD

The present invention relates to a thermoplastic elastomer compositionexcellent in moldability, heat resistance, weather resistance, chemicalresistance, adhesivity, flexibility and abrasion resistance. Further,the present invention relates to a composition for powder slash moldingand a powder slash molded article using the composition.

BACKGROUND ART

It is known that an acrylic block copolymer having methyl methacrylateas a hard segment and butyl acrylate as a soft segment has properties asa thermoplastic elastomer. For example, the mechanical properties of anacrylic block copolymer having a methacryl block and an acryl blockwhich is produced by an iniferter method are disclosed (Patent Reference1).

The acrylic block copolymer has characteristics excellent in weatherresistance, heat resistance, durability, oil resistance and abrasionresistance. Further, an elastomer which is extremely soft in comparisonwith other thermoplastic elastomers such as a styrene block copolymercan be provided by suitably selecting components composing the blockcopolymer.

As uses making use of the properties of the acrylic block copolymer,there has been expected development as various superficial skinmaterials, interior materials, and a material for a part which isdirectly touched by a hand making use of smooth feeling thereof.

As physical properties necessary for these superficial skin materials,there are resistance to chemicals which may be possibly contacted,further, the adhesivity of superficial skin with a substrate when thesuperficial skin and the substrate are directly adhered, the adhesivityof the superficial skin with a buffer material when the buffer materialis provided between the superficial skin and the substrate, in additionto mechanical properties, scratch resistance, heat resistance, strainrestorability. As the molding method of the superficial skin materials,the powder slash molding using soft powder material which is a powdermolding method is widely adopted for the superficial skin of interiorequipments for an automobile such as an instrument panel, a console boxand a door trim. This is caused by that they have soft texture, skincrepe and stitch can be provided, further, the degree of freedom indesign is large, and designing property is satisfactory. Since a formingpressure is not applied in the molding method, differing from othermolding methods such as injection molding and compression molding, it isa condition that powder flowability is excellent because the powdermaterial is required to be uniformly adhered on a mold with acomplicated shape at molding and simultaneously, it is also a conditionthat melt viscosity is low because powder adhering on a mold is meltedand a film is required to be formed by flowing under no pressure. As thematerial, a polyvinyl chloride sheet has been conventionally widely usedbecause it is excellent in hardness of a surface in use and flexibility,but since a polyvinyl chloride resin contains a lot of chlorine in itsmolecules, there is fear of great adverse effect on environments and aneffective substitute material is desired (Patent Reference 2).Accordingly, a sheet molded article of a thermoplastic elastomer hasbeen conventionally developed as the substitution of the polyvinylchloride resin (Patent Reference 3, Patent Reference 4, and PatentReference 5). However, sheets using a polyolefin resin and a styreneelastomer are insufficient in abrasion resistance, flexibility and oilresistance. Further, a sheet using thermoplastic polyurethane was poorin moldability, and also has a problem from the viewpoint of the costthereof.

-   Patent Reference 1: Japanese Patent No. 2553134-   Patent Reference 2: JP-A-5-279485-   Patent Reference 3: JP-A-7-82433-   Patent Reference 4: JP-A-10-30036-   Patent Reference 5: JP-A-2000-103957

DISCLOSURE OF INVENTION

An object of the present invention is to obtain an acrylic blockcopolymer composition improving melt flowability at molding and beingexcellent in heat resistance in addition to maintain weather resistance,chemical resistance, adhesivity, flexibility and abrasion resistancewhich are the characteristics of the acrylic block copolymer.

As a result of repeating intensive studies in order to solve theabove-mentioned problems, the present inventors have found that theproblems can be effectively solved by converting the acrylic blockcopolymer to having a high molecular weight or crosslinking the acrylicblock copolymer at molding, and reached the present invention.

Namely, the present invention relates to a thermoplastic elastomercomposition comprising an acrylic block copolymer (A) which comprises amethacrylic polymer block (a) and an acrylic polymer block (b), whereinat least one of polymer blocks among the methacrylic polymer block (a)and the acrylic polymer block (b) has an acid anhydride group and/or acarboxyl group, and an acrylic polymer (B) having 1.1 or more of epoxygroups in one molecule.

A preferable embodiment relates to the thermoplastic elastomercomposition, wherein the acid anhydride group and/or the carboxyl groupexist in the main chain of the acrylic block copolymer (A) and the acidanhydride group is represented by the general formula (1):

(Wherein R¹ is hydrogen or a methyl group and may be the same ordifferent. n is an integer of 0 to 3 and m is an integer of 0 or 1).

A preferable embodiment relates to the thermoplastic elastomercomposition, wherein the acrylic block copolymer (A) comprises 10 to 60%by weight of the methacrylic polymer block (a) in which a methacrylicpolymer is the main component and 90 to 40% by weight of the acrylicpolymer block (b) in which an acrylic polymer is the main component.

A preferable embodiment relates to the thermoplastic elastomercomposition, wherein the acrylic polymer block (b) comprises 50 to 100%by weight of at least one monomer selected from the group consisting ofn-butyl acrylate, ethyl acrylate and 2-methoxyethyl acrylate and 50 to0% by weight of other acrylate ester and/or other vinyl monomercopolymerizable with these monomers.

A preferable embodiment relates to the thermoplastic elastomercomposition, wherein the number average molecular weight measured by gelpermeation chromatography of the acrylic block copolymer (A) is 30,000to 200,000.

A preferable embodiment relates to the thermoplastic elastomercomposition, wherein a ratio (Mw/Mn) of the weight average molecularweight (Mw) to the number average molecular weight (Mn) measured by gelpermeation chromatography of the acrylic block copolymer (A) is 1.8 orless.

A preferable embodiment relates to the thermoplastic elastomercomposition, wherein the acrylic block copolymer (A) is a blockcopolymer produced by atom transfer radical polymerization.

A preferable embodiment relates to the thermoplastic elastomercomposition, wherein the glass transition temperature of the methacrylicpolymer block (a) is 25 to 130° C.

A preferable embodiment relates to the thermoplastic elastomercomposition, wherein the weight average molecular weight of the acrylicpolymer (B) is 30,000 or less.

A preferable embodiment relates to the thermoplastic elastomercomposition, wherein a glass transition temperature of the acrylicpolymer (B) is 100° C. or less.

A preferable embodiment relates to the thermoplastic elastomercomposition, wherein the acrylic polymer (B) comprises 50 to 100% byweight of at least one monomer selected from the group consisting ofn-butyl acrylate, ethyl acrylate and 2-methoxyethyl acrylate and 50 to0% by weight of other acrylate ester and/or other vinyl monomercopolymerizable with these monomers.

A preferable embodiment relates to the thermoplastic elastomercomposition, wherein the weight average molecular weight of the acrylicpolymer (B) is 500 to 10,000.

A preferable embodiment relates to the thermoplastic elastomercomposition, wherein viscosity of the acrylic polymer (B) is 35,000mPa·s or less.

A preferable embodiment relates to the thermoplastic elastomercomposition, wherein 5 to 200 parts by weight of a filler is furtheradded based on 100 parts by weight of the acrylic block copolymer.

A preferable embodiment relates to the thermoplastic elastomercomposition, wherein 0.1 to 20 parts by weight of a lubricant is furtheradded based on 100 parts by weight of the acrylic block copolymer.

The present invention relates to a thermoplastic elastomer compositionfor powder slash molding, comprising the above-mentioned composition.

The present invention relates to a molded article, which is obtained bypowder slash molding the above-mentioned composition.

The present invention relates to a superficial skin for an automobileinterior, which is obtained by powder slash molding the above-mentionedcomposition.

EFFECT OF THE INVENTION

An acrylic block copolymer composition excellent in moldability and heatresistance in addition to maintain weather resistance, chemicalresistance, adhesivity, flexibility and abrasion resistance, which arethe characteristics of an acrylic block copolymer, can be obtained byusing the present invention. Further, the composition of the presentinvention can be preferably used for powder slash molding.

BEST MODE FOR CARRYING OUT THE INVENTION

The present invention is further explained in detail in the following.

The present invention is characterized in comprising an acrylic blockcopolymer (A) which comprises a methacrylic polymer block (a) and anacrylic polymer block (b), wherein at least one of polymer blocks amongthe methacrylic polymer block (a) and the acrylic polymer block (b) hasan acid anhydride group and/or a carboxyl group, and an acrylic polymer(B) having 1.1 or more of epoxy groups in one molecule. The acidanhydride group and/or the carboxyl group are usually reacted with theepoxy group at molding, whereby the acrylic block copolymer (A) isconverted to having a high molecular weight or crosslinked.

<Acrylic Block Copolymer (A)>

The structure of the acrylic block copolymer (A) of the presentinvention is a linear block copolymer or a branched (star shape) blockcopolymer and a mixture thereof. The structure of the block copolymermay be used depending on the physical properties of the acrylic blockcopolymer (A) required, but the linear block copolymer is preferablefrom the viewpoints of cost and easiness of polymerization. The linearblock copolymer may be any structure. When the methacrylic polymer block(a) is represented as “a” and the acrylic polymer block (b) isrepresented as “b”, it is preferable that at least one acrylic blockcopolymer selected from the group consisting of (a-b)_(n) type,b-(a-b)_(n) type and (a-b)_(n)-a type (n is an integer of at least 1,for example, an integer of 1 to 3), from the viewpoint of the physicalproperties of the linear block copolymer or the physical properties ofthe composition. It is not particularly limited, but among those, an a-btype diblock copolymer, an a-b-a type triblock copolymer, or a mixturethereof is preferable from the viewpoints of easiness of handling atprocessing and the physical properties of the composition.

It is characteristic that at least one of the acid anhydride groupand/or the carboxyl group is introduced in at least one polymer block ofthe methacrylic polymer block (a) and the acrylic polymer block (b).When its number is 2 or more, the mode in which the monomer ispolymerized may be random copolymerization or block copolymerization.When the a-b-a type triblock copolymer is represented as an example, anyof a (a/z)-b-a type, a (a/z)-b-(a/z) type, a z-a-b-a type, a z-a-b-a-ztype, an a-(b/z)-a type, an a-b-z-a type, an a-z-b-z-a type, a(a/z)-(b/z)-(a/z) type, and a z-a-z-b-z-a-z type may be satisfactory.Herein z represents a monomer or a polymer block containing an acidanhydride group and/or a carboxyl group, (a/z) represents that a monomercontaining an acid anhydride group and/or a carboxyl group iscopolymerized with the methacrylic polymer block (a) and (b/z)represents that a monomer containing an acid anhydride group and/or acarboxyl group is copolymerized in the acrylic polymer block (b).

Further, a site containing z and a mode of containing z in themethacrylic polymer block (a) or the acrylic polymer block (b) may befreely set, and can be used in accordance with a purpose.

The number average molecular weight of the acrylic block copolymer (A)is not particularly limited, and may be determined from molecular weightrespectively necessary for the methacrylic polymer block (a) and theacrylic polymer block (b). When the molecular weight is small, there maybe a case where mechanical properties enough as an elastomer cannot beexpressed, and adversely when the molecular weight is large more thannecessity, there may be a case where processing property is lowered.Since flowage under non pressurization is required in particular in caseof the powder slash molding, when the molecular weight is large, meltviscosity is enhanced and moldability tends to be deteriorated. From theabove-mentioned viewpoint, the number average molecular weight of theacrylic block copolymer (A) is preferably 30,000 to 200,000, morepreferably 35,000 to 150,000, and further preferably 40,000 to 100,000.

The ratio (Mw/Mn) of the weight average molecular weight to the numberaverage molecular weight measured by gel permeation chromatography ofthe acrylic block copolymer (A) is not particularly limited, but ispreferably 1.8 or less and more preferably 1.5 or less. When Mw/Mnexceeds 1.8, there may be a case where uniformity of the acrylic blockcopolymer is deteriorated.

The composition ratio of the methacrylic polymer block (a) to theacrylic polymer block (b) which form the acrylic block copolymer (A) is5 to 90% by weight of the block (a) and 95 to 10% by weight of the block(b). The range of the composition ratio is preferably 10 to 60% byweight of (a) and 90 to 40% by weight of (b), and further preferably 15to 50% by weight of (a) and 85 to 50% by weight of (b) from theviewpoints of retention of a shape at molding and elasticity as anelastomer. When the proportion of (a) is less than 5% by weight, theshape tends to be hardly retained at molding and when the proportion of(b) less than 10% by weight, elasticity as an elastomer and meltingproperty at molding tend to be lowered.

Since when the proportion of (a) is small, hardness tends to be low andwhen the proportion of (b) is small, hardness tends to be high, from theviewpoint of hardness of the elastomer composition, the proportion canbe set according to the hardness of the required elastomer composition.Further, since when the proportion of (a) is small, viscosity tends tobe low, and when the proportion of (b) is small, viscosity tends to behigh, from the viewpoint of the processing, the proportion can be setaccording to the required processing property.

The relation of glass transition temperatures between the methacrylicpolymer block (a) and the acrylic polymer block (b) which form theacrylic block copolymer (A) preferably satisfies the relation of thefollowing formula, referring to the glass transition temperature of themethacrylic polymer block (a) as Tg_(a) and referring to the glasstransition temperature of the acrylic polymer block (b) as Tg_(b).Tg_(a)>Tg_(b)

The setting of the glass transition temperature (Tg) of theabove-mentioned polymer (the methacrylic polymer block (a) and acrylicpolymer block (b)) can be carried out by setting the weight ratio of amonomer at respective polymer portions according to the following Foxformula.1/Tg=(W ₁ /Tg ₁)+(W ₂ /Tg ₂)+ - - - +(W _(m) /Tg _(m))W ₁ +W ₂ + - - - +W _(m)=1

Wherein Tg represents the glass transition temperature of a polymerportion and Tg₁, Tg₂, - - - , Tg_(m) represent the glass transitiontemperatures of respective polymerization monomers. Further, W₁,W₂, - - - , W_(m) represent weight ratios of respective polymerizationmonomers.

As the glass transition temperatures of respective polymerizationmonomers in the above-mentioned Fox formula, for example, valuesdescribed in Polymer Handbook Third Edition (Wiley-Interscience, 1989)may be used.

Further, the glass transition temperature can be measured by DSC(Differential Scanning Caloriemeter) or the tan δ peak of dynamicviscoelasticity, but when polarity between the methacrylic polymer block(a) and the acrylic polymer block (b) is too near and the chain numberof block monomers is too little, there may be a case where thosemeasurement values are deviated from the calculation formula by theabove-mentioned Fox formula.

<Acid Anhydride Group and Carboxyl Group>

In the present invention, the acid anhydride group and carboxyl groupare enough to act as a reaction point with the acrylic polymer (B),preferably acts as a reaction point for converting a block copolymer tohaving a high molecular weight or a crosslinking point for crosslinkingthe block copolymer. Either of the acid anhydride group and the carboxylgroup may be contained in the acrylic block copolymer (A), and both ofthem may be contained together. It may be suitably selected from theviewpoints such as easiness of the reaction, easiness of theintroduction to the acrylic block copolymer (A), and cost thereof.

The acid anhydride group and carboxyl group are introduced into theblock copolymer by a form protecting the functional group with anappropriate protecting group or a form of the precursors of the acidanhydride group and the carboxyl group and then, the acid anhydridegroup and the carboxyl group can be also prepared by known chemicalreactions.

The acid anhydride group and the carboxyl group may be contained in onlyone block of either of the methacrylic polymer block (a) and the acrylicpolymer block (b), may be contained in both blocks, and can be used sothat the introduction condition of the acid anhydride group and thecarboxyl group is preferable in accordance with purposes such as thereaction point of the acrylic block copolymer (A), the cohesive forceand glass transition temperature of the block (the methacrylic polymerblock (a) and the acrylic polymer block (b)) composing the acrylic blockcopolymer (A) and further the required physical property of the acrylicblock copolymer (A).

For example, when the methacrylic polymer block (a) and the acrylicpolymer block (b) are wanted to be selectively reacted with the acidanhydride group and the carboxyl group as reaction points using theacrylic polymer (B) which has reactivity with the acid anhydride groupand the carboxyl group, the acid anhydride group and the carboxyl groupmay be introduced in blocks to be reacted.

Further, the acid anhydride group and/or the carboxyl group may beintroduced in the methacrylic polymer block (a) from the viewpoints ofthe improvement of heat resistance and thermal decomposition resistanceof the acrylic block copolymer (A), and the acid anhydride group and/orthe carboxyl group may be introduced into the acrylic polymer block (b)as reaction points from the viewpoints of imparting oil resistance,further rubber elasticity and compression set durability to the acrylicblock copolymer (A). Not particularly limited, it is preferable thateither of the block of the methacrylic polymer block (a) or the acrylicpolymer block (b) has the acid anhydride group and/or the carboxyl groupfrom the viewpoints of the control of reaction points, heat resistance,rubber elasticity, mechanical strength, and flexibility.

The content number of the acid anhydride group and/or the carboxyl groupis varied depending on the cohesive force and reactivity of the acidanhydride group and/or the carboxyl group, the structure and compositionof the acrylic block copolymer (A), the number of blocks composing theacrylic block copolymer (A), the glass transition temperature, and thesite at which the acid anhydride group and/or the carboxyl group iscontained and the mode thereof. Consequently, it may be set according tonecessity, and preferably 1.0 or more per one molecule of the blockcopolymer, and more preferably 2.0 or more. When the number is less than1.0, the improvement of heat resistance by converting to having a highmolecular weight by a bimolecular reaction of the block copolymer orcrosslinking tend to be insufficient.

When the acid anhydride group and/or the carboxyl group is introducedinto the methacrylic polymer block (a), it is preferable to beintroduced within a range in which the moldability of the acrylic blockcopolymer (A) is not lowered. Since flowage under no pressurization isrequired particularly in case of the powder slash molding, the cohesiveforce and the glass transition temperature Tg of the methacrylic polymerblock (a) are increased by the introduction of the acid anhydride groupand/or the carboxyl group; therefore, melt viscosity is increased andmoldability tends to be deteriorated. Specifically, it is preferable tobe introduced within a range in which the glass transition temperatureTg of the methacrylic polymer block (a) after introduction of the acidanhydride group and/or the carboxyl group is preferably 130° C. or less,more preferably 110° C. or less, and further preferably 100° C. or less.

When the acid anhydride group and/or the carboxyl group is introducedinto the acrylic polymer block (b), it is preferably introduced within arange not deteriorating the flexibility, rubber elasticity and lowtemperature property of the acrylic block copolymer (A). When thecohesive force and the glass transition temperature Tg of the acrylicpolymer block (b) are increased by introducing the acid anhydride groupand/or the carboxyl group, the flexibility, rubber elasticity and lowtemperature property tend to be deteriorated. Specifically, it ispreferable to be introduced within a range in which the glass transitiontemperature of the acrylic polymer block (b) after the introduction ofthe acid anhydride group and/or the carboxyl group is preferably 25° C.or less, more preferably 0° C. or less, and further preferably −20° C.or less.

An acid anhydride group and a carboxyl group are explained in thefollowing.

<Acid Anhydride Group>

When a compound having an active proton is contained in the composition,the acid anhydride group is easily reacted with an epoxy group. The acidanhydride group is not particularly limited, but it may be introducedinto the main chain of the acrylic block copolymer (A) and may beintroduced into side chains. The acid anhydride group is the acidanhydride group of a carboxyl group, and it is preferably introducedinto the main chain from the viewpoint of easiness of introduction intothe acrylic block copolymer (A). Specifically, it is represented by thegeneral formula (1). It is contained in a form represented by thegeneral formula (1):

(wherein R¹ is hydrogen or a methyl group and may be mutually the sameor different. n is an integer of 0 to 3 and m is an integer of 0 or 1).

n in the general formula (1) is an integer of 0 to 3, preferably 0 or 1and more preferably 1. When n is 4 or more, polymerization becomescomplicated or cyclization of the acid anhydride group tends to bedifficult.

As the introduction method of the acid anhydride group, it is preferableto be introduced into the acrylic block copolymer in a form which is theprecursor of the acid anhydride group, and thereafter cyclized. Notparticularly limited, but it is preferable to melt-knead the acrylicblock copolymer which has at least one unit represented by the generalformula (2) to be introduced by cyclization;

(wherein R² represents hydrogen or a methyl group. R³ representshydrogen, a methyl group or a phenyl group, at least 2 among 3 of R³'sare selected from a methyl group and/or a phenyl group and 3 of R³'s maybe mutually the same or different).

The introduction of the unit represented by the general formula (2) tothe acrylic block copolymer can be carried out by copolymerizing anacrylic acid ester or a methacrylic acid ester monomer derived from thegeneral formula (2). Examples of the monomer are t-butyl (meth)acrylate,isopropyl (meth)acrylate, α,α-dimethylbenzyl (meth)acrylate,α-methylbenzyl (meth)acrylate, but is not limited thereto. Among those,t-butyl (meth)acrylate is preferable from the viewpoints such asavailability, easiness of polymerizability, and easiness of generatingthe acid anhydride group.

For the formation of the acid anhydride group, the acrylic blockcopolymer having the precursor of the acid anhydride group is preferablyheated under high temperature and preferably heated at 180 to 300° C.When the temperature is lower than 180° C., generation of the acidanhydride group tends to be insufficient, and when it is higher than300° C., the acrylic block copolymer in itself having a precursor of theacid anhydride group tends to be decomposed.

<Carboxyl Group>

The carboxyl group is easily reacted with an epoxy group. The carboxylgroup is not particularly limited, but it may be introduced in the mainchain of the acrylic block copolymer (A) or may be introduced in a sidechain. The carboxyl group is preferably introduced in the main chainfrom the viewpoint of easiness of the introduction into the acrylicblock copolymer (A).

Concerning the introduction method of carboxyl group, when a monomerhaving a carboxyl group does not poison a catalyst under polymerizationconditions, the carboxyl group is preferably introduced directly bypolymerization, and when a monomer having a carboxyl group deactivatesthe catalyst at polymerization, a method of introducing the carboxylgroup by converting a functional group is preferable.

In the method of introducing the carboxyl group by converting afunctional group, the carboxyl group is introduced into the acrylicblock copolymer in the form of protecting the carboxyl group with anappropriate protecting group or in the form of a functional group beingthe precursor of the carboxyl group, and then the functional group canbe prepared by known chemical reactions. The carboxyl group can beintroduced by the method.

As the synthesis method of the acrylic block copolymer (A) having acarboxyl group, for example, there are a method by which an acrylicblock copolymer containing a monomer having a functional group such ast-butyl methacrylate or trimethylsilyl methacrylate, which is theprecursor of the carboxyl group, is synthesized, and the carboxyl groupis formed by known chemical reactions such as hydrolysis or aciddecomposition (JP-A-10-298248 and JP-A-2001-234146), and a method whicha acrylic block copolymer having at least one unit represented by thegeneral formula (2) is melt-kneaded and a carboxyl group is introduced;

(wherein R² represents hydrogen or a methyl group. R³ representshydrogen, a methyl group or a phenyl group, at least 2 among 3 of R³'sare selected from a methyl group and/or a phenyl group, and 3 of R³'smay be mutually the same or different). The unit represented by thegeneral formula (2) has a route in which a carboxyl group is generatedby decomposing the ester unit under a high temperature, andsuccessively, cyclization occurs to generate the acid anhydride group.By utilizing this, the carboxyl group can be introduced by appropriatelyadjusting heating temperature and time in accordance with the kind andcontent of the unit represented by the general formula (2).

Further, the carboxyl group can be also introduced by hydrolysis of theacid anhydride group.

<Methacrylic Polymer Block (a)>

The methacrylic polymer block (a) is a block obtained by polymerizing amonomer comprising a methacrylic acid ester as the main component, andpreferably comprises 50 to 100% by weight of the methacrylic acid esterand 0 to 50% by weight of a vinyl monomer copolymerizable with this.Further, a monomer having the acid anhydride group and/or the carboxylgroup may be contained as the methacrylic acid ester. When theproportion of the methacrylic acid ester is less than 50% by weight,there is a case where weather resistance which are a characteristic ofthe methacrylic acid ester is deteriorated.

Examples of the methacrylic acid ester composing the methacrylic polymerblock (a) are methacrylic acid aliphatic hydrocarbon (for example, alkylhaving 1 to 18 carbons) esters such as methyl methacrylate, ethylmethacrylate, n-propyl methacrylate, n-butyl methacrylate, isobutylmethacrylate, n-pentyl methacrylate, n-hexyl methacrylate, n-heptylmethacrylate, n-octyl methacrylate, 2-ethylhexyl methacrylate, nonylmethacrylate, decyl methacrylate, dodecyl methacrylate and stearylmethacrylate; methacrylic acid alicyclic hydrocarbon esters such ascyclohexyl methacrylate and isobornyl methacrylate; methacrylic acidaralkyl esters such as benzyl methacrylate; methacrylic acid aromatichydrocarbon esters such as phenyl methacrylate and tolyl methacrylate;esters of methacrylic acid with alcohol containing a functional grouphaving ethereal oxygen such as 2-methoxyethyl methacrylate and3-methoxybutyl methacrylate; methacrylic acid fluorinated alkyl esterssuch as trifluoromethyl methacrylate, trifluoromethylmethylmethacrylate, 2-trifluoromethylethyl methacrylate, 2-trifluoroethylmethacrylate, 2-perfluoroethylethyl methacrylate,2-perfluoroethyl-2-perfluorobutylethyl methacrylate, 2-perfluoroethylmethacrylate, perfluoromethyl methacrylate, diperfluoromethylmethylmethacrylate, 2-perfluoromethyl-2-perfluoroethylmethyl methacrylate,2-perfluorohexylethyl methacrylate, 2-perfluorodecylethyl methacrylateand 2-perfluorohexadecylethyl methacrylate. At least one of these isused. Among those, methyl methacrylate is preferable from the viewpointsof processability, cost, and availability.

Examples of the vinyl monomer copolymerizable with a methacrylic acidester composing the methacrylic polymer block (a) are an acrylic acidester, an aromatic alkenyl compound, a vinyl cyanide compound, aconjugated diene compound, a halogen-containing unsaturated compound, anunsaturated carboxylic acid compound, an unsaturated dicarboxylic acidcompound, a vinyl ester compound, and a maleimide compound.

Examples of the acrylic acid ester are acrylic acid aliphatichydrocarbon (for example, alkyl having 1 to 18 carbons) esters such asmethyl acrylate, ethyl acrylate, n-propyl acrylate, n-butyl acrylate,isobutyl acrylate, n-pentyl acrylate, n-hexyl acrylate, n-heptylacrylate, n-octyl acrylate, 2-ethylhexyl acrylate, nonyl acrylate, decylacrylate, dodecyl acrylate and stearyl acrylate; acrylic acid alicyclichydrocarbon esters such as cyclohexyl acrylate and isobornyl acrylate;acrylic acid aromatic hydrocarbon esters such as phenyl acrylate andtolyl acrylate; acrylic acid aralkyl esters such as benzyl acrylate;esters of acrylic acid with alcohol containing a functional group havingethereal oxygen such as 2-methoxyethyl acrylate and 3-methoxybutylacrylate; acrylic acid fluorinated alkyl esters such astrifluoromethylmethyl acrylate, 2-trifluoromethylethyl acrylate,2-perfluoroethylethyl acrylate, 2-perfluoroethyl-2-perfluorobutylethylacrylate, 2-perfluoroethyl acrylate, perfluoromethyl acrylate,diperfluoromethylmethyl acrylate,2-perfluoromethyl-2-perfluoroethylmethyl acrylate, 2-perfluorohexylethylacrylate, 2-perfluorodecylethyl acrylate and 2-perfluorohexadecylethylacrylate.

Examples of the aromatic alkenyl compound are styrene, α-methylstyrene,p-methylstyrene, and p-methoxystyrene.

Examples of the vinyl cyanide compound includes acrylonitrile, andmethacrylonitrile.

Examples of the conjugated diene compound are butadiene and isoprene.

Examples of the halogen-containing unsaturated compound are vinylchloride, vinylidene chloride, perfluoroethylene, perfluoropropylene,and vinylidene fluoride.

Examples of the unsaturated carboxylic acid compound are methacrylicacid and acrylic acid.

Examples of the unsaturated dicarboxylic acid compound are maleicanhydride, maleic acid, a monoalkyl ester and a dialkyl ester of maleicacid, fumaric acid, and a monoalkyl ester and a dialkyl ester of fumaricacid.

Examples of the vinyl ester compound are vinyl acetate, vinylpropionate, vinyl pivalate, vinyl benzoate, and vinyl cinnamate.

Examples of the maleimide compound are maleimide, methylmaleimide,ethylmaleimide, propylmaleimide, butylmaleimide, hexylmaleimide,octylmaleimide, dodecylmaleimide, stearylmaleimide, phenylmaleimide, andcyclohexylmaleimide.

At least one of these is used. Among those vinyl monomers, a preferablemonomer can be selected from the viewpoints such as adjustment of aglass transition temperature required for the methacrylic polymer block(a), and compatibility with the acrylic polymer block (b).

The glass transition temperature of the methacrylic polymer block (a) ispreferably 25 to 130° C., more preferably 40 to 110° C., and furtherpreferably 50 to 100° C. from the viewpoints of thermal deformation andmoldability of the elastomer composition.

From the above-mentioned viewpoints, the methacrylic polymer block (a)is preferably a block obtained by polymerizing methyl methacrylate asthe main component, a monomer having the acid anhydride group and/or thecarboxyl group and at least one monomer selected from the groupconsisting of ethyl acrylate, n-butyl acrylate, and 2-methoxyethylacrylate for controlling a glass transition temperature.

Tg_(a) of the methacrylic polymer block (a) can be set by setting aweight ratio of monomers in a polymer portion according to theabove-mentioned Fox formula.

<Acrylic Polymer Block (b)>

The acrylic polymer block (b) is a block obtained by polymerizing amonomer which comprises an acrylic acid ester as the main component, andpreferably comprises 50 to 100% by weight of an acrylic acid ester and 0to 50% by weight of a vinyl monomer copolymerizable with this. Further,a monomer having the acid anhydride group and/or the carboxyl group maybe contained as an acrylic acid ester. When the proportion of theacrylic acid ester is less than 50% by weight, there may be a case wherethe physical property of the composition, in particular, flexibility andoil resistance, which are the characteristics of using the acrylic acidester, is damaged.

Examples of an acrylic acid ester composing the acrylic polymer block(b) are monomers similar to the acrylic acid ester, which is exemplifiedas a monomer composing the methacrylic polymer block (a).

These can be used alone or in combination of two or more kinds thereof.Among those, n-butyl acrylate is preferable from the viewpoint of thebalance of rubber elasticity, property at low temperature and cost. Whenoil resistance and mechanical property are required, ethyl acrylate ispreferable. Further, when imparting low temperature property and oilresistance and improvement of surface tackiness of a resin are required,2-methoxyethyl acrylate is preferable. Further, when the balance of oilresistance and the low temperature property is required, a combinationof ethyl acrylate, n-butyl acrylate, and 2-methoxyethyl acrylate ispreferable.

Example of the vinyl monomer copolymerizable with an acrylic acid estercomposing the acrylic polymer block (b) are a methacrylic acid ester, anaromatic alkenyl compound, a vinyl cyanide compound, a conjugated dienecompound, a halogen-containing unsaturated compound, asilicon-containing unsaturated compound, an unsaturated carboxylic acidcompound, an unsaturated dicarboxylic acid compound, a vinyl estercompound, and a maleimide compound. Specific examples thereof are thosesame as the above-mentioned compounds used for the methacrylic polymerblock (a).

At least one of these is used. Among those vinyl monomers, a preferablemonomer can be selected from the viewpoint of the balance of glasstransition temperature and oil resistance required for the acrylicpolymer block (b), and compatibility with the methacrylic polymer block(a). For example, acrylonitrile can be copolymerized for the purpose ofimproving oil resistance of the composition.

The glass transition temperature of the acrylic polymer block (b) ispreferably at most 25° C., more preferably at most 0° C., and furtherpreferably at most −20° C. from the viewpoint of rubber elasticity ofthe elastomer composition. When the glass transition temperature of theacrylic polymer block (b) is higher than the temperature of environmentin which the elastomer composition is used, it is not advantageousbecause rubber elasticity is hardly expressed.

From the above-mentioned viewpoints, the acrylic polymer block (b) ispreferably a block obtained by polymerizing the acid anhydride groupand/or the carboxyl group and a monomer comprising at least one monomerselected from the group consisting of n-butyl acrylate, ethyl acrylateand 2-methoxyethyl acrylate as the main component.

Tg_(b) of the acrylic polymer block (b) can be set by setting the weightratio of each of monomers in a polymer according to the above-mentionedFox formula.

<Preparation Process of Acrylic Block Copolymer (A)>

The process for preparing the acrylic block copolymer (A) is notparticularly limited, but controlled polymerization using an initiatorfor a polymer is preferably used. Examples of the controlledpolymerization are living anion polymerization, radical polymerizationusing a chain transfer agent and living radical polymerization which hasbeen recently developed. Among those, the living radical polymerizationis preferable from the viewpoint of controlling a molecular weight and astructure of the acrylic block copolymer.

The living radical polymerization is radical polymerization in whichactivity of the terminal of polymerization is maintained without losing.The living polymerization indicates polymerization in which the terminalalways continues to have activity in the narrow sense, but in general,pseudoliving polymerization in which the terminal deactivated and theterminal activated are in equilibrium state is also included. Thedefinition herein is also applied to the latter. Recently, the livingradical polymerization has been actively studied by various groups.

Example of the living radical polymerization are those using a chaintransfer agent such as polysulfide, those using a cobalt porphyrincomplex (J. Am. Chem. Soc., 1994, Vol. 116, page 7943), those using aradical capturing agent such as a nitroxide compound (Macromolecules,1994, Vol. 27, page 7228), and Atom Transfer Radical Polymerization(ATRP) using a transition metal complex as a catalyst and organichalogenated compound as an initiator. In the present invention, there isno limitation for which method is used, but the Atom Transfer RadicalPolymerization is preferable from the viewpoint of easiness of control.

The Atom Transfer Radical Polymerization is carried out by using anorganic halogenated compound or a halogenated sulfonyl compound as aninitiator and a metal complex in which Group VII, Group VIII, Group IX,Group X or Group XI element of the Periodic Table is used as a centralmetal, as a catalyst (for example, refer to Matyjaszewski et. al., J.Am. Chem. Soc., 1995, Vol. 117, page 5614, Macromolecules, 1995, Vol.28, page 7901, Science, 1996, Vol. 272, page 866 or Sawamoto et. al.,Macromolecules, 1995, Vol. 28, page 1721).

According to the method, in general, even though it is radicalpolymerization in which polymerization speed is very high and atermination reaction such as the coupling of mutual radicals easilyoccurs, but the polymerization livingly proceeds, a polymer with narrowmolecular weight distribution (Mw/Mn=1.1 to 1.5) is obtained and amolecular weight can be freely controlled by changing the ratio of amonomer and an initiator.

In the Atom Transfer Radical Polymerization, as the organic halogenatedcompound or halogenated sulfonyl compound as an initiator,monofunctional, bifunctional or multifunctional compounds can be used.These may be used in accordance with its purpose, but when a diblockcopolymer is produced, a monofunctional compound is preferable from theviewpoint of easy availability of an initiator. When a triblockcopolymer of a-b-a type and a triblock copolymer of b-a-b type areproduced, a bifunctional compound is preferably used from the viewpointof reducing the number of reaction steps and time. When a branched blockcopolymer is produced, a multifunctional compound is preferably usedfrom the viewpoint of reducing the number of reaction steps and time.

Further, a macroinitiator can be also used as the above-mentionedinitiator. The polymer initiator is a compound comprising a polymer inwhich a halogen atom is bonded at the terminal of a molecule, among theorganic halogenated compound or the halogenated sulfonyl compound. Sincesuch macroinitiator can be also produced by the controlledpolymerization method other than the living radical polymerizationprocess, there is a characteristic that a block copolymer bonded with apolymer obtained by a different polymerization process is obtained.

Examples of the monofunctional compound are compounds represented by

-   C₆H₅—CH₂X,-   C₆H₅—C(H)(X)—CH₃,-   C₆H₅—C(X)(CH₃)₂,-   R⁴—C(H)(X)—COOR⁵,-   R⁴—C(CH₃)(X)—COOR⁵,-   R⁴—C(H)(X)—CO—R⁵,-   R⁴—C(CH₃)(X)—CO—R⁵, and-   R⁴—C₆H₄—SO₂X.

Wherein, C₆H₅ represents a phenyl group and C₆H₄ represents a phenylenegroup (it may be either of ortho substitution, meta substitution andpara substitution). R⁴ represents a hydrogen atom, an alkyl group having1 to 20 carbons, an aryl group having 6 to 20 carbons or an aralkylgroup having 7 to 20 carbons. X represents chlorine, bromine or iodine.R⁵ represents a monovalent organic group having 1 to 20 carbons.

As R⁴, the specific example of an alkyl group (including a alicyclichydrocarbon group) having 1 to 20 carbons includes a methyl group, anethyl group, a propyl group, an isopropyl group, a n-butyl group, anisobutyl group, a tert-butyl group, a n-pentyl group, a n-hexyl group, acyclohexyl group, a n-heptyl group, a n-octyl group, a 2-ethylhexylgroup, a nonyl group, a decyl group, a dodecyl group, and an isobornylgroup. The specific example of an aryl group having 6 to 20 carbonsincludes a phenyl group, a tolyl group, and a naphthyl group. Specificexamples of an aralkyl group having 7 to 20 carbons are a benzyl groupand a phenethyl group.

Specific examples of a monovalent organic group having 1 to 20 carbonsbeing R⁵ are groups similar as R⁴.

Specific examples of the mono functional compound are tosyl bromide,methyl 2-bromopropionate, ethyl 2-bromopropionate, butyl2-bromopropionate, methyl 2-bromoisobutyrate, ethyl 2-bromoisobutyrate,and butyl 2-bromoisobutyrate. Among those, ethyl 2-bromopropionate andbutyl 2-bromopropionate are preferable from the viewpoint of easiness ofcontrolling polymerization because they are similar as the structure ofan acrylic acid ester monomer.

Examples of the bifunctional compound are compounds represented by

-   X—CH₂—C₆H₄—CH₂—X,-   X—CH(CH₃)—C₆H₄—CH(CH₃)—X,-   X—C(CH₃)₂—C₆H₄—C(CH₃)₂—X,-   X—CH(COOR⁶)—(CH₂)_(n)—CH(COOR⁶)—X,-   X—C(CH₃)(COOR⁶)—(CH₂)_(n)—C(CH₃)(COOR⁶)—X,-   X—CH(COR⁶)—(CH₂)_(n)—CH(COR⁶)—X,-   X—C(CH₃)(COR⁶)—(CH₂)_(n)—C(CH₃)(COR⁶)—X,-   X—CH₂—CO—CH₂—X,-   X—CH(CH₃)—CO—CH(CH₃)—X,-   X—C(CH₃)₂—CO—C(CH₃)₂—X,-   X—CH(C₆H₅)—CO—CH(C₆H₅)—X,-   X—CH₂—COO—(CH₂)_(n)—OCO—CH₂—X,-   X—CH(CH₃)—COO—(CH₂)_(n)—OCO—CH(CH₃)—X,-   X—C(CH₃)₂—COO—(CH₂)_(n)—OCO—C(CH₃)₂—X,-   X—CH₂—CO—CO—CH₂—X,-   X—CH(CH₃)—CO—CO—CH(CH₃)—X,-   X—C(CH₃)₂—CO—CO—C(CH₃)₂—X,-   X—CH₂—COO—C₆H₄—OCO—CH₂—X,-   X—CH(CH₃)—COO—C₆H₄—OCO—CH(CH₃)—X,-   X—C(CH₃)₂—COO—C₆H₄—OCO—C(CH₃)₂—X, and-   X—SO₂—C₆H₄—SO₂—X.

Wherein R⁶ represents an allyl group having 1 to 20 carbons, an arylgroup having 6 to 20 carbons or an aralkyl group having 7 to 20 carbons.The n represents an integer of 0 to 20. C₆H₅, C₆H₄ and X are similar asthe above-description.

Specific examples of an allyl group having 1 to 20 carbons, an arylgroup having 6 to 20 carbons and an aralkyl group having 7 to 20 carbonsof R⁶ are the same as the specific examples of an alkyl group having 1to 20 carbons, an aryl group having 6 to 20 carbons or an aralkyl grouphaving 7 to 20 carbons of R⁴.

Specific example of the bifunctional compound arebis(bromomethyl)benzene, bis(1-bromoethyl)benzene,bis(1-bromoisopropyl)benzene, dimethyl 2,3-dibromosuccinate, diethyl2,3-dibromosuccinate, dibutyl 2,3-dibromosuccinate, dimethyl2,4-dibromoglutarate, diethyl 2,4-dibromoglutarate, dibutyl2,4-dibromoglutarate, dimethyl 2,5-dibromoadipate, diethyl2,5-dibromoadipate, dibutyl 2,5-dibromoadipate, dimethyl2,6-dibromopimelate, diethyl 2,6-dibromopimelate, dibutyl2,6-dibromopimelate, dimethyl 2,7-dibromosuberate, diethyl2,7-dibromosuberate, and dibutyl 2,7-dibromosuberate. Among those,bis(bromomethyl)benzene, diethyl 2,5-dibromoadipate and diethyl2,6-dibromopimelate are preferable from the viewpoint of theavailability of raw materials.

Examples of the multifunctional compound are compounds represented by

-   C₆H₃—(CH₂—X)₃,-   C₆H₃—(CH(CH₃)—X)₃,-   C₆H₃—(C(CH₃)₂—X)₃,-   C₆H₃—(OCO—CH₂—X)₃,-   C₆H₃—(OCO—CH(CH₃)—X)₃,-   C₆H₃—(OCO—C(CH₃)₂—X)₃, and-   C₆H₃—(SO₂—X)₃.

Wherein C₆H₃ is a trivalent phenyl group (the position of three bondinghands may be a combination of either of 1-position to 6-position) and Xis the same as the above description.

Specific examples of the multifunctional compound aretris(bromomethyl)benzene and tris(1-bromoethyl)benzene,tris(1-bromoisopropyl)benzene. Among those, tris(bromomethyl)benzene ispreferable from the viewpoint of the availability of raw materials.

Further, when the organic halogenated compound or halogenated sulfonylcompound having a functional group other than a group initiatingpolymerization is used, a polymer in which a functional group other thana group initiating polymerization is introduced at a terminal or in amolecule can be easily obtained. The functional group other than a groupinitiating polymerization includes an alkenyl group, a hydroxyl group,an epoxy group, an amino group, an amide group, and a silyl group.

As the organic halogenated compound or halogenated sulfonyl compoundwhich can be used as the initiator, carbon atom with which a halogengroup (a halogen atom) is bonded with a carbonyl group or a phenyl groupand carbon-halogen bond is activated to initiate polymerization. Anamount of the initiator used may be determined from the molar ratio witha monomer in conformity with a molecular weight of the acrylic blockcopolymer required. Namely, the molecular weight of the acrylic blockcopolymer can be controlled by what molecule of a monomer is used per 1molecule of the initiator.

The transition metal complex used as the catalyst of the Atom TransferRadical Polymerization is not particularly limited, but preferableexamples are the complex of monovalent or zero-valent copper, thecomplex of bivalent ruthenium, the complex of bivalent iron and thecomplex of bivalent nickel.

Among those, the complex of copper is preferable from the viewpoints ofcost and reaction control. Examples of the monovalent copper are cuprouschloride, cuprous bromide, cuprous iodide, cuprous cyanide, cuprousoxide, and cuprous perchlorate. Among those, cuprous chloride andcuprous bromide are preferable from the viewpoint of the control ofpolymerization. When the monovalent copper compound is used,2,2′-bipyridyl compounds such as 2,2′-bipyridyl and its derivative (suchas 4,4′-dinolyl-2,2′-bipyridyl and 4,4′-di(5-nolyl)-2,2′-bipyridyl);1,10-phenanthroline compounds such as 1,10-phenanthroline and itsderivative (such as 4,7-dinolyl-1,10-phenanthroline and5,6-dinolyl-1,10-phenanthroline); polyamines such astetramethylethylenediamine (TMEDA), pentamethyldiethylenetriamine andhexamethyl(2-aminoethyl) amine may be added as a ligand in order toenhance activation of catalyst.

Further, the tristriphenylphosphin complex (RuCl₂(PPh₃)₃) of bivalentruthenium chloride is also preferable as a catalyst. When the rutheniumcompound is used as a catalyst, an aluminum alkoxides may be added as anactivating agent. Further, the bistriphenylphosphine complex(FeCl₂(PPh₃)₂) of bivalent iron, the bistriphenylphosphine complex(NiCl₂(PPh₃)₂) of bivalent nickel and the bistributylphosphine complex(NiBr₂(PPh₃)₂) of bivalent nickel are also preferable as a catalyst.

The catalyst, ligand and activator used are not particularly limited,but they may be suitably determined by the relation between reactionspeed and the initiator, monomer and solvent used. For example, since itis preferable for the polymerization of acrylic monomers such as anacrylic acid ester that the growth terminal of polymer chains has acarbon-bromine bond from the viewpoint of controlling a polymerization,it is preferable that the initiator used is the organic brominatedcompound or brominated sulfonyl compound and the solvent isacetonitrile, and it is more preferable that a ligand such aspentamethyldiethylenetriamine is used, and a metal complex catalyst inwhich cupric bromide, preferably copper contained in cuprous bromide isa central metal is used. Further, since it is preferable from theviewpoint of controlling polymerization that the growth terminal ofpolymer chains has a carbon-chloride bond for the polymerization ofmethacrylic monomers such as a methacrylic acid ester, the initiatorused is the organic chlorinated compound or chlorinated sulfonylcompound, and the solvent is acetonitrile or a mix solvent with tolueneif necessary, and it is more preferable that a ligand such aspentamethyldiethylenetriamine is used and a metal complex catalyst inwhich cupric chloride, preferably copper contained in cuprous chlorideis a central metal is used.

The amounts of the catalyst and ligand used may be determined from therelation between required reaction speed and the amounts of theinitiator, monomer and solvent used. For example, when a polymer with ahigh molecular weight is obtained, the ratio of the initiator to themonomer must be smaller than a case of obtaining a polymer with lowmolecular weight, but in such a case, the reaction speed can beincreased by increasing the catalyst and ligand. Further, when a polymerhaving a higher glass transition temperature than a room temperature isprepared, an appropriate organic solvent is added for enhancing stirringefficiency by lowering the viscosity of the system. Therefore, thereaction speed tends to be lowered, but in such a case, the reactionspeed can be increased by increasing the catalyst and ligand.

The Atom Transfer Radical Polymerization can be carried out innon-solvent (bulk polymerization) or in various solvents. Further, whenpolymerization is carried out by bulk polymerization or in varioussolvents, the polymerization can be also stopped on the way.

As the solvent, for example, a hydrocarbon solvent, an ether solvent, ahalogenated hydrocarbon solvent, a ketone solvent, an alcohol solvent, anitrile solvent, an ester solvent, and a carbonate solvent can be used.

The hydrocarbon solvent includes benzene and toluene. The ether solventincludes diethyl ether and tetrahydrofuran. The halogenated hydrocarbonsolvent includes methylene chloride and chloroform. The ketone solventincludes acetone, methyl ethyl ketone, and methyl isobutyl ketone. Thealcohol solvent includes methanol, ethanol, propanol, isopropanol, andn-butanol and tert-butanol. The nitrile solvent includes acetonitrile,propionitrile, and benzonitrile. The ester solvent includes ethylacetate and butyl acetate. The carbonate solvent includes ethylenecarbonate and propylene carbonate.

One or more of the solvents mentioned above can be used.

When the solvent is used, the amount used may be suitably determinedfrom the relation between the viscosity of the whole system and stirringefficiency required. Further, when polymerization is carried out by bulkpolymerization or in various solvents, the conversion of a monomer atstopping the reaction may be suitably determined from the relationbetween the viscosity of the whole system and required stirringefficiency, even if the polymerization is stopped on the way.

The polymerization can be carried out in a range of 23° C. to 200° C.and preferably in a range of 50° C. to 150° C.

In order to produce the acrylic block copolymer by the polymerization,there are mentioned a method of successively adding a monomer, a methodof polymerizing the next block using a polymer preliminarilysynthesized, as a macroinitiator, a method of bonding polymersseparately polymerized by a reaction. Either of these methods may beused and may be used in accordance with purposes. The method ofsuccessively adding a monomer is preferable from the viewpoint ofsimplicity and easiness of the preparation steps.

The reaction solution obtained by the polymerization contains a mixtureof a polymer and the metal complex. An organic acid containing acarboxyl group or a sulfonyl group is added thereto to prepare a saltwith the metal complex, and the solid of the salt with the metal complexprepared is removed by filtration, successively, impurities such as anacid remaining in the solution are removed by basic active alumina, abasic absorbent, a solid inorganic acid, an anion exchange resin andcellulose anion exchanger adsorption treatment and thereby, the solutionof the acrylic block copolymer can be obtained.

The polymerization solvent and unreacted monomer are successivelyremoved by evaporation from the polymer solution obtained in thismanner, and the acrylic block copolymer is isolated. As the evaporationsystem, a thin film evaporation system, a flash evaporation system, ahorizontal type evaporation system equipped with an extrusion screw canbe used. Since the acrylic block copolymer has adhering property,efficient evaporation can be carried out by the horizontal typeevaporation system equipped with an extrusion screw alone or acombination with other evaporation system among the above-mentionedevaporation systems.

<Acrylic Polymer (B)>

The acrylic polymer (B) composing the thermoplastic elastomercomposition relating to the present invention is a polymer containing1.1 or more of epoxy groups in one molecule. It improves moldingflowability as a plasticizer at molding the composition, andsimultaneously reacts with the acid anhydride group and/or the carboxylgroup in the acrylic block copolymer (A), and can convert the acrylicblock copolymer (A) to having a high molecular weight by aninter-bimolecular reaction or crosslinking. The number mentioned hererepresents the average number of the epoxy groups existing in the wholeof the acrylic polymer (B)

The content number of the epoxy groups in the acrylic polymer (B) ischanged depending on the reactivity of the epoxy groups, a site in whichthe epoxy groups are contained and its mode, and the number of the acidanhydride group and/or the carboxyl group in the acrylic block copolymer(A), sites in which the acid anhydride group and/or the carboxyl groupis contained and its mode. Accordingly, it may be set according torequirement, but is 1.1 or more in the acrylic polymer (B), morepreferably 1.5 or more, and particularly preferably 2.0 or more. When itis less than 1.1, an effect as a high molecular weight-convertingreaction agent for the bimolecular reaction of the block copolymer and acrosslinking agent is low and the improvement of heat resistance of theacrylic block copolymer (A) tends to be insufficient.

The acrylic polymer (B) is preferably a polymer obtained by polymerizing1 or at least 2 kinds of acrylic monomers or polymerizing a mixture of 1or at least 2 kinds of acrylic monomers with other monomers other thanthe acrylic monomers.

The acrylic monomer includes an acryloyl group-containing monomer and amethacryloyl group-containing monomer, and the specific examples aremethyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate,butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, cyclohexyl(meth)acrylate, (meth)acrylic acid, hydroxyethyl (meth)acrylate,hydroxypropyl (meth)acrylate, glycidyl (meth)acrylate, 2-methoxyethyl(meth)acrylate, 2-ethoxyethyl (meth)acrylate, 2-butoxyethyl(meth)acrylate, and 2-phenoxyethyl (meth)acrylate. Further, in thepresent specification, (meth)acrylate means acryl or methacryl. As theabove-mentioned other monomers, a monomer copolymerizable with the acrylbase monomer, for example, vinyl acetate, and styrene can be used.

The acrylic polymer (B) includes an acryloyl group-containing monomerunit. The proportion of the monomer unit containing an acryloyl group tothe total monomer unit in the acrylic polymer (B) is preferably at least70% by weight. When the proportion is less than 70% by weight, weatherresistance of the polymer is comparatively low and compatibility withthe acrylic block copolymer (A) tends to be lowered. Further,discoloration is easily caused in the molded article.

The acrylic polymer (B) is preferably obtained by polymerizing 50 to100% by weight of at least one monomer selected from the groupconsisting of n-butyl acrylate, ethyl acrylate and 2-methoxyethylacrylate and 50 to 0% by weight of other acrylate ester and/or othervinyl monomer copolymerizable with these monomers. As the vinyl monomer,styrene is preferable.

Further, the weight average molecular weight of the acrylic polymer (B)is not particularly limited, but preferably a polymer having a lowmolecular weight of 30,000 or less, further preferably a polymer of 500to 30,000, and particularly preferably a polymer of 500 to 10,000. Whenthe weight average molecular weight is less than 500, a molded articletends to be sticky and on the other hand, when the weight averagemolecular weight exceeds 30,000, the polymer tends to hardly plasticizea molded article.

The viscosity of the acrylic polymer (B) is preferably 35,000 mPa·s ormore at measuring with a cone plate type rotational viscometer (E typeviscometer) at 25° C. More preferable viscosity is 10,000 mPa·s or more.Particularly preferable viscosity is 5,000 mPa·s or more. When theviscosity is higher than 35,000 mPa·s, the plasticizer hardlyplasticizes a molded article. There is no particular lower limit ofpreferable viscosity, but the usual viscosity of the acrylic polymer is10 mPa·s or more.

The glass transition temperature Tg of the acrylic polymer (B) measuredby a differential scanning caloriemeter (DSC) is preferably 100° C. orless, more preferably 25° C. or less, further preferably 0° C. or less,and particularly preferably −30° C. or less. When the glass transitiontemperature Tg exceeds 100° C., tendency for improving moldability as aplasticizer is lowered, and flexibility of the obtained molded articletends to be lowered.

The acrylic polymer (B) can be prepared by polymerizing by knownprocesses. The polymerization process is not particularly limited, andcan be carried out by, for example, suspension polymerization, emulsionpolymerization, bulk polymerization, living anion polymerization, andcontrolled polymerization such as polymerization using a chain transferagent and living radical polymerization, but a process in which acomparatively low molecular weight polymer with satisfactory weatherresistance and heat resistance can be obtained is preferable, and aprocess by using high temperature continuous polymerization described inthe flowing is more preferable from the viewpoint of the cost thereof.

The acrylic polymer (B) is preferably obtained by polymerizationreaction at a temperature of 180 to 350° C. Since a comparatively lowmolecular weight polymer is obtained at the polymerization temperaturewithout a polymerization initiator and a chain transfer agent, theobtained acrylic polymer is an excellent plasticizer and satisfactory inweather resistance. The specific examples are processes by hightemperature continuous polymerization disclosed in JP-A-57-502171,JP-A-59-6207, JP-A-60-215007 and WO 01/083619. Namely, it is a processin which a mixture of the above-mentioned monomers is continuously fedat a fixed speed to a reactor which is set at a fixed temperature andpressure and the reaction solution in conformity with the feed amount isextracted.

As the acrylic polymer (B), specifically, ARUFON XG4000, ARUFON XG4010,ARUFON XD945, ARUFON XD950, ARUFON UG4030, and ARUFON UG4070 of TOAGOSEICo., Ltd. can be favorably exemplified.

These are acrylic polymers such as all acryl and acrylate/styrene and1.1 or more of the epoxy groups are contained in a molecule.

The acrylic polymer (B) is preferably used in a range of 0.1 to 100parts by weight based on 100 parts by weight of the acrylic blockcopolymer (A), more preferably a range of 1 to 50 parts by weight, andparticularly preferably a range of 1.5 to 20 parts by weight. When thecompounding amount is less than 0.1 parts by weight, moldability andheat resistance of the obtained molded article may occasionallyinsufficient and when it exceeds 100 parts by weight, the mechanicalproperty of the obtained composition tends to be lowered.

<Thermoplastic Elastomer Composition>

The thermoplastic elastomer composition of the present invention is lowin melt viscosity at molding and excellent in moldability, and on theother hand, the acid anhydride group and/or carboxyl group in theacrylic block copolymer (A) is reacted with an epoxy group in theacrylic polymer (B) at molding, and the acrylic block copolymer (A) ispreferably converted to having a high molecular weight or crosslinked.It is more preferable to crosslink it at molding from the viewpoint ofthe improvement of heat resistance.

In the thermoplastic elastomer composition of the present invention,various additives and a catalyst may be added if necessary in order toaccelerate a reaction at molding. For example, curing agents such asacid anhydride base such as acid dianhydride, amine base and imidazolebase which are generally used for an epoxy resin can be also used.

In the thermoplastic elastomer composition of the present invention, afiller is compounded if necessary, and it can be preferably used. Thefiller is not particularly limited, and examples are reinforcing fillerssuch as wood flour, pulp, cotton chip, asbestos, glass fiber, carbonfiber, mica, walnut shell flour, rice hull flour, graphite, diatomearth, white clay, silica (fumed silica, precipitating silica, crystalsilica, fused silica, dolomite, silicic anhydride, hydrated silicicacid) and carbon black; fillers such as heavy calcium carbonate,colloidal calcium carbonate, magnesium carbonate, diatom earth, calcinedclay, clay, talc, titanium oxide, bentonite, organic bentonite, ferricoxide, colcothar, aluminum fine powder, flint powder, zinc oxide, activezinc oxide, zinc powder, zinc carbonate and sand bur balloon; fibrousfillers such as asbestos, glass fiber and glass filament, carbon fiber,Kevlar fiber and polyethylene fiber.

Among those fillers, inorganic fillers are more preferable from theviewpoints of the improvement of mechanical property, reinforcingeffect, cost, and titanium oxide, carbon black, calcium carbonate,silica and talc are further preferable.

Further, in case of silica, silica on which the surface is preliminarilyhydrophobically treated with organosilicone compounds such asorganosilanes, organosilazane and diorganopolysiloxane may be used.Further, as calcium carbonate, there may be also used calcium carbonatein which surface treatment is carried out using surface treating agentssuch as organic substances such as fatty acids, fatty acid soap andfatty acid esters; various surfactants, and various coupling agents suchas a silane coupling agent and a titanate coupling agent.

An amount to be added in the case of using the filler is preferably in arange of 5 to 200 parts by weight based on 100 parts by weight of theacrylic block copolymer (A), and more preferably in a range of 10 to 100parts by weight. When the amount is less than 5 parts by weight, thereinforcing effect of the obtained molded article is occasionally notsufficient, and when it exceeds 200 parts by weight, moldability of thecomposition tends to be lowered. At least one filler can be used.

The thermoplastic elastomer composition of the present invention cancompound various lubricants for moldability, mold releasing property andfor making the surface of a molded article low frictional, and it can bepreferably used.

The lubricant includes fatty acids such as stearic acid and palmiticacid; metal salts of fatty acids such as calcium stearate, zincstearate, magnesium stearate, potassium palmitate and sodium palmitate;waxes such as polyethylene wax, polypropylene wax and montanic acid wax;low molecular weight polyolefins such as low molecular weightpolyethylene and low molecular weight polypropylene; polyorganosioxanessuch as dimethylpolysiloxane; cucutadecylamine, alkyl phosphate, fattyacid esters, amide lubricants such as ethylenebisstearylamide, fluorineresin powder such as ethylene tetrafluoride resin, molybdenum disulfidepowder, silicone resin powder, silicone rubber powder, and silica. Atleast one kind of these can be used. Among those, stearic acid, zincstearate, calcium stearate, fatty acid esters, ethylenebisstearylamidewhich are excellent in cost and moldability are preferable.

An amount to be added in the case of using the lubricant is preferablyin a range of 0.1 to 20 parts by weight based on 100 parts by weight ofthe acrylic block copolymer (A), and more preferably in a range of 0.2to 20 parts by weight. When the compounding amount is less than 0.1 partby weight, the improving effect of moldability and making the obtainedmolded article have low friction are occasionally not sufficient, andwhen it exceeds 20 parts by weight, the mechanical property and chemicalresistance of the obtained molded article tend to be deteriorated. Atleast one lubricant can be used.

In the thermoplastic elastomer composition of the present invention,various additives other than those described above may be added ifnecessary, for the purpose of the adjustment of various physicalproperties of the thermoplastic elastomer composition and the obtainedmolded article. As the additives, a stabilizer, a plasticizer, aflexibility imparting agent, a flame retardant, a pigment, an antistaticagent, an antibacterial and antifungus agent may be added.

As the above-mentioned stabilizer, an antioxidant, a photo stabilizer,and an ultraviolet absorbent are raised. Examples of antioxidant areamine antioxidants such as phenyl-α-naphthylamine (PAN),octyldiphenylamine, N,N′-diphenyl-p-phenylenediamine (DPPD),N,N′-di-β-naphthyl-p-phenylenediamine (DNPD),N-(1,3-dimethylbutyl)-N′-phenyl-p-phenylenediamine,N-phenyl-N′-isopropyl-p-phenylenediamine (IPPN),N,N′-diallyl-p-phenylenediamine, phenothiazine derivative,diallyl-p-phenylenediamine mixture, alkylated phenylenediamine,4,4′-bis(α,α-dimethylbenzyl)diphenylamine,N-phenyl-N′-(3-methacryloyloxy-2-hydropropyl)-p-phenylenediamine,diallylphenylenediamine mixture, diallyl-p-phenylenediamine mixture,N-(1-methylheptyl)-N′-phenyl-p-phenylenediamine and diphenylaminederivative; imidazole antioxidants such as 2-mercaptobenzoimidazole(MBI); phenol antioxidants such as 2,6-di-t-butyl-4-methylphenol andpentaerythrityltetrakis[3-(5-di-t-butyl-4-hydroxyphenol)-propionate];phosphate antioxidants such as nickel diethyl-dithiocarbamate; thesecondary antioxidants such as triphenylphosphite;2-t-butyl-6-(3-t-butyl-2-hydroxy-5-methylbenzyl)-4-methylphenylacrylate, and2-[1-(2-hydroxy-3,5-di-t-pentylphenyl)ethyl]-4,6-di-t-pentylphenylacrylate. Further, examples of the photo stabilizer and ultravioletabsorbent are 4-t-butylphenyl salicylate, 2,4-dihydroxybenzophenone,2,2′-dihydroxy-4-methoxybenzophenone, ethyl-2-cyano-3,3′-diphenylacrylate, 2-ethylhexyl-2-cyano-3,3′-diphenyl acrylate,2-hydroxy-5-chlorobenzophenone,2-hydroxy-4-methoxybenzophenone-2-hydroxy-4-octoxybenzophenone,monoglycol salicylate, oxalic amide, and2,2′,4,4′-tetrahydroxybenzophenone.

Examples of industrial products are Irganox 1010 (available from ChibaSpecialty Chemicals Co., Ltd.), SANOL LS770 (available from SANKYOLifetech Co., Ltd.), ADEKA STAB LA-57 (available from ADEKACorporation), ADEKA STAB LA-68 (available from ADEKA Corporation),Chimassorb 944 (available from Chiba Specialty Chemicals Co., Ltd.),SANOL LS765 (available from SANKYO Lifetech Co., Ltd.), ADEKA STAB LA-62(available from ADEKA Corporation), TINUVIN 144 (available from ChibaSpecialty Chemicals Co., Ltd.), ADEKA STAB LA-63 (available from ADEKACorporation), TINUVIN 622 (available from Chiba Specialty Chemicals Co.,Ltd.), ADEKASTAB LA-32 (available from ADEKA Corporation), ADEKA STABLA-36 (available from ADEKA Corporation), TINUVIN 571 (available fromChiba Specialty Chemicals Co., Ltd.), TINUVIN 234 (available from ChibaSpecialty Chemicals Co., Ltd.), ADEKA STAB LA-31 (available from ADEKACorporation), TINUVIN 1130 (available from Chiba Specialty ChemicalsCo., Ltd.), ADEKA STAB AO-20 (available from ADEKA Corporation), ADEKASTAB AO-50 (available from ADEKA Corporation), ADEKA STAB 2112(available from ADEKA Corporation), ADEKA STAB PEP-36 (available fromADEKA Corporation), SUMILIZER GM (available from Sumitomo Chemical Co.,Ltd.), SUMILIZER GS (available from Sumitomo Chemical Co., Ltd.), andSUMILIZER TP-D (available from Sumitomo Chemical Co., Ltd.). These maybe used alone and at least two kinds thereof may be used in combination.Among those, SANOL LS770, Irganox 1010, SUMILIZER GS and TINUVIN 234 arepreferable from the viewpoints of the prevention effect of deteriorationby heat and light of the acrylic block and the cost thereof.

Example of the above-mentioned plasticizer are phthalic acid derivativessuch as dimethyl phthalate, diethyl phthalate, di-n-butyl phthalate,di-(2-ethylhexyl) phthalate, diheptyl phthalate, diisodecyl phthalate,di-n-octyl phthalate, diisononyl phthalate, ditridecyl phthalate,octyldecyl phthalate, butylbenzyl phthalate and dicyclohexyl phthalate;isophthalic acid derivatives such as dimethyl isophthalate;tetrahydrophthalic acid derivatives such as di-(2-ethylhexyl)tetrahydrophthalate; adipic acid derivatives such as dimethyl adipate,dibutyl adipate, di-n-hexyl adipate, di-(2-ethylhexyl) adipate, isononyladipate, diisodecyl adipate and dibutyldiglycol adipate; azelaic acidderivatives such as di-(2-ethylhexyl) azelate; sebacic acid derivativessuch as dibutyl sebacate; dodecan-2-ic acid derivatives; maleic acidderivatives such as dibutyl maleate and di-(2-ethylhexyl) maleate;fumaric acid derivatives such as dibutyl fumarate; trimellitic acidderivatives such as tris-(2-ethylhexyl) trimellitate; pyromellitic acidderivatives; citric acid derivatives such as acetyltributyl citrate;itaconic acid derivatives; oleic acid derivatives; ricinoleic acidderivatives; stearic acid derivatives; other fatty acid derivatives;sulfonic acid derivatives; phosphoric acid derivatives; glutaric acidderivatives; polyester plasticizers which are polymers of dibasic acidssuch as adipic acid, azelaic acid and phthalic acid with glycol andmonovalent alcohol; glycol derivatives; glycerin derivatives; paraffinderivatives such as chlorinated paraffin; epoxy derivative polyesterpolymerization type plasticizers; polyether polymerization typeplasticizers; carbonate derivatives such as ethylene carbonate andpropylene carbonate. The plasticizer in the present invention is notlimited thereto, various plasticizers can be used and those which arewidely commercially available as a plasticizer for rubber can be alsoused. It can be expected that these compounds can lower the viscosity ofthe acrylic block copolymer (A). Examples of commercially availableplasticizers are THIOCOL TP (available from Morton Co.), ADEKACIZERO-130P, C-79, UL-100, P-200, and RS-735 (available from ADEKACorporation). Examples of a high molecular weight plasticizer other thanthose are acrylic polymer, polypropylene glycol polymer,polytetrahydrofuran polymer, and polyisobutylene polymer. It is notparticularly limited, but among those, adipic acid derivatives, phthalicacid derivatives, glutaric acid derivatives, trimellitic acidderivatives, pyromellitic acid derivatives, polyether plasticizers,glycerin derivatives, epoxy derivative polyester polymerization typeplasticizers, polyether polymerization type plasticizers are preferablesince they have low volatility and weight loss thereof by heating issmall.

The above-mentioned flexibility imparting agent is not particularlylimited, and examples are a softening agent such as process oil; oilsuch as animal oil and plant oil; petroleum fractions such as kerosene,light oil, heavy oil and naphtha. As the softening agent, process oil ismentioned, and more specific examples are paraffin oil; naphtheneprocess oil; and petroleum process oil such as aromatic process oil. Asthe plant oil, examples are ricinus oil, cotton seed oil, linseed oil,rape seed oil, soy bean oil, palm oil, coconut oil, peanut oil, pineoil, and tall oil, and at least one of these flexibility impartingagents can be used.

As the above-mentioned flame retardant, the following compounds can bementioned but they are not particularly limited, and examples aretriphenyl phosphate, tricresyl phosphate, decabromobiphenyl,decabromobiphenyl ether, and antimony trioxide. These can be used alone,or a plurality of these may be used in combination.

As the above-mentioned pigment, the following compounds can be mentionedbut they are not particularly limited, and examples are carbon black,titanium oxide, zinc sulfide, and zinc oxide. These can be used alone,or a plurality of these may be used in combination.

<Preparation Process of Thermoplastic Elastomer Composition>

The preparation process of thermoplastic elastomer composition is notparticularly limited, but for example, as a batch type kneading device,a mixing roll, a Banbury mixer, a pressuring kneader and a high shearingmixer can be used, and as a continuous kneading equipment, a uniaxialextruder, a biaxial extruder, and a KCK extruder may be used. Further,known processes such as a process of mechanically mixing a compositionto be formed in pellets can be used.

A temperature at kneading for preparing the thermoplastic elastomercomposition is preferably a temperature at which the acrylic blockcopolymer (A) is reacted with acrylic polymer (B) and moldability is notlowered. A temperature at which the acrylic block copolymer (A) isreacted with acrylic polymer (B) and moldability is deteriorated isdetermined by kinds of the acid anhydride group, carboxyl group, epoxygroup, introduction amount, the composition of the acrylic blockcopolymer (A) and acrylic polymer (B), and the compatibility of theacrylic block copolymer (A) with acrylic polymer (B). Accordingly, thereaction is carried out at a desired temperature by changing theseconditions. Herein, the reaction temperature is preferably 200° C. orless for enabling molding of the obtained composition, more preferably180° C. or less, and further preferably 150° C. or less.

It is preferable to carry out processing at a temperature at which highmolecular weight conversion or crosslinking does not occur andprocessing can be carried out. But the temperature may be within a rangein which processing can be carried out, though high molecular weightconversion occurs in part or partial crosslinking occurs.

In the case of the powder slash molding, it is preferable to obtain thethermoplastic elastomer composition as powder. As the process ofobtaining powder, the powder can be obtained by finely pulverizing thethermoplastic elastomer composition in a block state or a pellet statewhich is processed by the above-mentioned process by using an impactpulverizer such as a turbo mill, a pin mill, a hammer mill and acentrifugation mill. At this time, pulverization is usually carried outat normal temperature, but mechanical pulverization can be carried outby using a cooling medium and a cooling facility.

<Molding Process of Thermoplastic Elastomer Composition>

The composition obtained in the above-described preparation process ofthe thermoplastic elastomer can be molded by various processes, and itcan be preferably applied to powder slash molding, injection molding,injection blow molding, blow molding, extrusion blow molding, extrusionmolding, calendar molding, vacuum molding, and press molding. Amongthem, the powder slash molding is more preferably used. Herein, thepowder slash molding is a process of flowing the composition powder intoa molding mold heated at a high temperature to be melt-molded and takingout a molded article solidified by cooling after taking a definiteperiod of time. It is required to fluidize the powder to carry outmelt-molding even under no pressurization in the powder slash molding,but on the other hand, the molded article after molding is exposed inenvironments where the molded article is used at 100° C. or more.Therefore it is difficult to make a balance between moldability and heatresistance. However, since the acrylic block copolymer (A) and theacrylic polymer (B) in the thermoplastic elastomer composition of thepresent invention are in an unreacted state before molding, and (B)effectively works as a plasticizer, thereby the composition is excellentin melting property in a mold. On the other hand, the acrylic blockcopolymer (A) is reacted with the acrylic polymer (B) within a definiteperiod of time until it is solidified by cooling, the acrylic blockcopolymer (A) is converted to having a high molecular weight orcrosslinked, and heat resistance after the molding is improved.Consequently, the thermoplastic elastomer composition can be recognizedas a preferable material for the powder slash molding.

When heat resistance is imparted by the high molecular weight conversionof the acrylic block copolymer (A) at molding in the powder slashmolding, the number average molecular weight of the acrylic blockcopolymer (A) after molding is preferably 100,000 or more, morepreferably 150,000 or more and further preferably 200,000 or more. Whenthe number average molecular weight is lower than 100,000, theimprovement effect of the heat resistance tends to be lowered.

Further, when the heat resistance is imparted by crosslinking atmolding, the insoluble content ratio (% by weight) of the molded articleafter molding is preferably 50% or more by weight, more preferably 70%or more by weight, and further more preferably 80% or more by weight.When the insoluble content ratio is lower than 50% by weight, theimprovement effect of the moldability and heat resistance tends to belowered. On the other hand, the insoluble content ratio before moldingis preferably 30% or less by weight, more preferably 10% or less byweight, and further preferably 5% or less by weight. When it is 30% byweight or more, moldability tends to be deteriorated.

In the above description, the insoluble content ratio (% by weight)represents the weight of a residual solid for 1 g of the thermoplasticelastomer composition. The residual solid is obtained by packing 1 g ofthe thermoplastic elastomer composition in a 350 mesh metal net,immersing it in toluene at 80° C. or acetone at 60° C. for 24 hours(toluene or acetone is selected by the solubility of the thermoplasticelastomer composition), fractionating a toluene or acetone soluble part,drying the residual solid at 80° C. under vacuum and measuring theweight g of the residual solid after drying.

EXAMPLES

The present invention is further explained in detail based on Examples,but the present invention is not limited only to these Examples.Further, BA, EA, MEA, MMA, TBMA, and TBA respectively represent n-butylacrylate, ethyl acrylate, 2-methoxyethyl acrylate, methyl methacrylate,t-butyl methacrylate, and t-butyl acrylate.

<Measurement Method of Molecular Weight>

Molecular weight shown in the present Example was calculated in terms ofpolystyrene which was measured by a GPC analysis device shown belowusing chloroform as mobile phase. A GPC system made by Waters Co. wasused as a system and Shodex k-804 (polystyrene gel) available from ShowaDenko K.K. was used as a column.

<Measurement Method of Conversion of Polymerization Reaction>

The conversion of a polymerization reaction shown in the presentExamples was measured by an analysis equipment and conditions shownbelow.

Device: Gas chromatography GC-14B made by Shimadzu Corporation.

Separation column: Capillary column; Supelcowax-10, 0.35 mmφ×30 m, madeby J & W SCIENTIFIC INC.

Separation condition: Initial temperature: 60° C. and retention for 3.5minutes.

-   -   Temperature increasing speed: 40° C./min    -   Final temperature: 140° C. and retention for 1.5 minutes    -   Injection temperature: 250° C.    -   Detector temperature: 250° C.        Sample adjustment: A sample was diluted to about 3-fold by ethyl        acetate and butyl acetate was used as an internal standard        substance.        <Measurement of Insoluble Content Ratio (% by Weight)>

1 g of the thermoplastic elastomer composition was packed in a 350 meshmetal net, and it was immersed in toluene at 80° C. or acetone at 60° C.for 24 hours (toluene or acetone is selected by the solubility of theacrylic block copolymer). Then, a toluene or acetone soluble part wasfractionated, the residual solid was dried at 80° C. under vacuum andthe weight g of the residual solid after drying was measured. Theinsoluble content ratio is represented by a weight of the residual solidcontent for 1 g of the thermoplastic elastomer composition.

<Ethanol Resistance Test>

Ethanol resistance shown in Examples and Comparative Examples wasmeasured according to conditions shown in the following.

The sheets with crepe pattern prepared in Examples and ComparativeExamples were placed on a flat surface, one drop of ethanol (availablefrom Wako Pure Chemical Industry Ltd.) was added dropwise with a pipettethereon, and they were left alone at a room temperature for 24 hours.Then, their surfaces were visually observed. The sheets were evaluatedby the criteria such that those having no trace were ◯, those in whichtrace was observed but had no whitening were Δ, and those in whichwhitening was observed were X.

<Oil Resistance Test>

Paraffin resistance property shown in Examples and Comparative Exampleswere measured by conditions shown in the following.

The sheets with crepe pattern prepared in Examples and ComparativeExamples were placed on a flat surface, one drop of liquid paraffin(available from Nakarai Tesk Co.) was added dropwise with a pipettethereon, and they were left alone at a room temperature for 24 hours.Then, the liquid paraffin was wiped off with KIMWIPE (made by CresiaInc.) and their surfaces were visually observed. The sheets wereevaluated by the criteria such that those having no trace were ◯, thosein which trace was observed but had no whitening were Δ, and those inwhich whitening was observed were X.

<Heat Resistance Test>

Heat resistance shown in Examples and Comparative Examples were measuredby conditions shown in the following.

The sheets with crepe pattern prepared in Examples and ComparativeExamples were left alone at 120° C. for 24 hours. Then, their surfaceswere visually observed. The sheets were evaluated by the criteria suchthat those in which the change of the crepe pattern was not observedwere ◯, those in which the change of the crepe pattern was not clear butsurface luster was increased in comparison with the initial stage wereΔ, and those in which the change of the crepe pattern was observed wereX.

<Urethane Adhesivity Test>

Superficial skin materials were prepared by press-molding thecompositions according to Examples. A cartridge type polyurethane(available from Air Tight Co.) in which 4,4′-diphenylmethanediisocyanatewas the main component was coated on a metal plate and the superficialskin material was immediately mounted on the foamed body to be adhered.After taking for at least 12 hours (state in which the foamed articlewas completely cured), the superficial skin material was peeled from thefoamed urethane with a hand and the state of destruction was observed.Those in which destruction occurred in a urethane material were referredto as ◯, those in which destruction occurred at the portion of interfacebetween a sheet and urethane were referred to as Δ, and those in whichdestruction occurred at interface between the sheet and urethane werereferred to as X.

<Powder Slash Property Test>

A block of the composition was prepared according to Examples andComparative Examples. The block of the composition was charged in asmall size pulverizer (made by Kyoritsu-Riko Co.) cooled with dry iceand pulverized while adding dry ice. The obtained powder was evaluatedunder condition in the following. The obtained powder was brought incontact for 30 seconds with a skin crepe metal plate heated at 260° C.,unmelted powder was removed after heat-melting and it was cooled to aroom temperature to obtain a molded sheet.

Evaluation Index:

The obtained molded sheet was observed visually. The sheet was evaluatedby the criteria such that those in which crepe transcription propertywas good and pinhole/foams were not found were referred to as ◯, thosein which either of one of items was poor were referred to as Δ, andthose in which the site of poor crepe formation was found andpinhole/foams were found were referred to as X.

Preparation Example 1 Synthesis of(MMA-co-BA-co-TBMA)-b-BA-b-(MMA-co-BA-co-TBMA) Type Acrylic BlockCopolymer (Hereinafter, Described as “the Precursor 1”)

The following operations were carried out in order to obtain theprecursor 1. After a 15 L pressure resistant reactor was purged withnitrogen, 13.6 g (95 mmol) of copper bromide was weighed and 146 g ofacetonitrile (treated with nitrogen bubbling) was added. After stirringby heating at 70° C. for 30 minutes, 19.0 g (53 mmol) of diethyl2,5-dibromoadipate as an initiator and 1664 g (13.0 mol) of BA wereadded. The mixture was stirred by heating at 85° C., and 1.65 g (9.5mmol) of pentamethyldiethylenetriamine as a ligand was added to initiatepolymerization.

About 0.2 mL of the polymerization solution as for sampling wasextracted from the polymerization solution periodically from the startof the polymerization, and the conversion of BA was determined by thegas chromatogram analysis of the sampling solution. A polymerizationspeed was controlled by adding pentamethyldiethylenetriamine as needed.When the conversion of BA reached 94.6%, 82.8 g (0.58 mol) of TBMA, 927g (9.3 mol) of MMA, 202 g (1.6 mol) of BA, 9.4 g (95 mmol) of copperchloride, 1.98 g (9.5 mmol) of pentamethyldiethylenetriamine and 2269 gof toluene (treated with nitrogen bubbling) were added thereto. Theconversion of TBMA, MMA and BA were determined in the same manner. Whenthe conversion of TBMA was 93.1%, the conversion of MMA was 89.2% andthe conversion of BA was 66.8% based on the concentration of BA justafter the addition of MMA/TBMA/BA, 2400 g of toluene was added, and thereactor was cooled with a water bath to terminate the reaction.

The polymerization solution was diluted with 1900 g of toluene, 32.5 gof p-toluene sulfonic acid monohydrate was added to be stirred for 3hours at a room temperature, and a precipitated solid was removed byfiltration. 40.8 g of an absorbent KYOWARD 500SH (available from KYOWAChemical Industry Co., Ltd.) was added to the obtained polymer solution,and the mixture was further stirred at a room temperature for one hour.The absorbent was filtered by a Kiriyama funnel to obtain a colorlesstransparent polymer solution. The solution was dried and the solvent andthe residual monomer were removed to obtain the precursor 1 which wasthe objective acrylic block copolymer.

When the GPC analysis of the precursor 1 of the acrylic block copolymerwas carried out, the number average molecular weight Mn was 72,200 andthe molecular weight distribution Mw/Mn was 1.42.

<Reaction Forming Acid Anhydride of Precursor 1>

45 g of the precursor 1 obtained in the above description and 0.09 g ofIrganox 1010 (available from Chiba Specialty Chemicals Co., Ltd.) weremelt-kneaded at 100 rpm for 20 minutes using a LABO Plasto Mill 50C150(blade shape: roller type R60, made by TOYO SEIKI KOGYO Co., Ltd.) setat 240° C. to obtain an objective acrylic block copolymer containing anacid anhydride group and a carboxyl group (hereinafter, the obtainedpolymer is described as “the polymer 1”).

The conversion to the acid anhydride group and the carboxyl group at at-butyl ester site could be confirmed by IR (infrared absorptionspectrum) and ¹³C(¹H)-NMR (nuclear magnetic resonance spectrum). Namely,in IR, it could be confirmed because absorption spectrum derived from anacid anhydride group was observed nearby 1800 cm⁻¹ after the conversion.In ¹³C(¹H)-NMR, it could be confirmed because a signal at 82 ppm whichwas derived from quaternary carbon of t-butyl group and a signal at 28ppm which was derived from methyl carbon of t-butyl group wereextinguished after the conversion and a signal at 172 to 173 ppm (m)which was derived from the carbonyl carbon of an acid anhydride groupand a signal at 176 to 179 ppm (m) which was derived from the carbonylcarbon of a carboxyl group newly appeared.

Preparation Example 2 Synthesis of(MMA-co-BA)-b-(BA-co-TBA)-b-(MMA-co-BA) Type Acrylic Block Copolymer(Hereinafter, Described as “the Precursor 2”)

The following operations were carried out in order to obtain theprecursor 2. After a 15 L pressure resistant reactor was purged withnitrogen, 7.89 g (55 mmol) of copper bromide, 830 g (6.5 mol) of BA and117 g (0.92 mol) of TBA were charged to start stirring. Then, a solutionin which 11.0 g (31 mmol) of diethyl 2,5-dibromoadipate as an initiatorwas dissolved in 83.3 g of acetonitrile (treated with nitrogen bubbling)was charged and the inner solution was stirred for 30 minutes whileraising a temperature to 75° C. When the inner temperature reached 75°C., 0.95 g (5 mmol) of pentamethyldiethylenetriamine as a ligand wasadded thereto to initiate the polymerization of an acrylic blockcopolymer.

About 0.2 mL of the polymerization solution as for sampling wasextracted from the polymerization solution by every fixed time from thestart of the polymerization, and the conversions of BA and TBA weredetermined by the gas chromatogram analysis of the sampling solution. Apolymerization speed was controlled by addingpentamethyldiethylenetriamine at the polymerization as needed.Pentamethyldiethylenetriamine was added 3 times in total (2.85 g intotal) during the polymerization of the acrylic polymer block.

When the conversion of BA reached 96.9% and the conversion of TBAreached 96.9%, 563 g (5.6 mol) of MMA, 127 g (1.0 mol) of BA, 5.44 g (55mmol) of copper chloride, 0.95 g (5 mmol) ofpentamethyldiethylenetriamine and 1287 g of toluene (treated withnitrogen bubbling) were added thereto to start the polymerization of themethacrylic polymer block.

The conversions of MMA and BA were determined in the same manner as atthe polymerization of the acrylic polymer block. Sampling was carriedout at charging MMA and BA, and the conversions of MMA and BA weredetermined using this as a basis. After charging MMA and BA, the innertemperature was set at 85° C. A polymerization speed was controlled byadding pentamethyldiethylenetriamine at polymerization as needed.Pentamethyldiethylenetriamine was added 4 times in total (3.8 g intotal) during the polymerization of the methacrylic polymer block. Whenthe conversion of MMA was 89.7% and the conversion of BA was 64.8%, 2400g of toluene was added and the reactor was cooled with a water bath toterminate the reaction.

Toluene was added to the obtained polymerization solution and it wasdiluted so that the concentration of the polymer was 25% by weight. 20.0g of p-toluene sulfonic acid monohydrate was added to the solution to bestirred for 3 hours at a room temperature, and a precipitated solid wasremoved by filtration.

33.0 g of an absorbent KYOWARD (trade mark) 500SH (available from KYOWAChemical Industry Co., Ltd.) was added to the obtained polymer solution,and the mixture was further stirred at a room temperature for one hour.The absorbent was filtered by a Kiriyama funnel to obtain a colorlesstransparent polymer solution. The solution was dried and the solvent andthe residual monomer were removed to obtain the precursor 2 which wasthe objective acrylic block copolymer.

When the GPC analysis of the obtained precursor 2 of the acrylic blockcopolymer was carried out, the number average molecular weight Mn was70,336, and the molecular weight distribution Mw/Mn was 1.44.

<Reaction Forming Acid Anhydride of Precursor 2>

700 g of the precursor 2 obtained in the above description, 4.2 g ofIrganox 1010 (available from Chiba Specialty Chemicals Co., Ltd.) and0.7 g of hydrotalcite DHT-4A-2 (available from KYOWA Chemical IndustryCo., Ltd.) as an acid trapping agent were compounded and melt-kneaded atabout 50 rpm for 50 minutes using a DS1-5MHB-E kneader (made by MORIYAMACo., Ltd.) set at 260° C. to obtain an objective acrylic block copolymercontaining an acid anhydride group and a carboxyl group (hereinafter,the obtained polymer is described as “the polymer 2”).

The measurement of conversion efficiency to the acid anhydride group andthe carboxyl group at t-butyl ester site was carried out by quantifyingthe amount of isobutylene generated from the t-butyl group by a thermaldecomposition reaction at 280° C. As a result of the measurement, theconversion efficiency of the obtained resin was at least 95%.

Preparation Example 3 Synthesis of(MMA-co-BA)-b-(BA-co-TBA)-b-(MMA-co-BA) Type Acrylic Block Copolymer(hereinafter, Described as “the Precursor 3”)

The following operations were carried out in order to obtain theprecursor 3.

A 500 L reactor purged with nitrogen was charged with 68.57 kg ofn-butyl acrylate, 6.40 kg of t-butyl acrylate and 0.625 kg of cuprousbromide to start stirring. Then, a solution in which 0.872 kg of diethyl2,5-dibromoadipate was dissolved in 6.59 kg of acetonitrile was charged,warm water was flowed into a jacket, and the solution was stirred for 30minutes while raising a temperature of the inner solution to 75° C. Whenthe inner temperature reached 75° C., 75.5 g ofpentamethyldiethylenetriamine was added thereto to initiate thepolymerization of an acrylic polymer block.Pentamethyldiethylenetriamine was added 3 times in total (226.5 g intotal) during the polymerization of the acrylic polymer block. Apolymerization speed was controlled by addingpentamethyldiethylenetriamine at the polymerization as needed.

When the conversion reached 97%, 101.7 kg of toluene, 0.431 kg ofcuprous chloride, 44.40 kg of methyl methacrylate, 10.07 kg of butylacrylate and 75.5 g of pentamethyldiethylenetriamine were added theretoto start the polymerization of the methacrylic polymer block. When theconversion of MMA reached 91%, 220 kg of toluene was added to dilute thereaction solution, and the reactor was cooled to terminate the reaction.When the GPC analysis of the obtained block copolymer was carried out,the number average molecular weight Mn was 74,900 and the molecularweight distribution Mw/Mn was 1.39.

30 kg of toluene was added to the obtained block copolymer solution, andthe concentration of the polymer was adjusted to 25% by weight. 1.74 kgof p-toluene sulfonic acid was added to the solution, the inside of thereactor was purged with nitrogen, and the solution was stirred for 3hours at 30° C. The reaction solution was sampled, and after confirmingthat the solution was colorless and transparent, 2.48 kg of RADIOLITE#3000 available from Showa Chemical Industry Co., Ltd. was addedthereto. Then, the reactor was pressurized to 0.1 to 0.4 MPaG withnitrogen, and a solid was separated using a pressure filtering machine(filtration area of 0.45 m²) equipped with polyester felt as afiltration material.

1.86 kg of KYOWARD 500SH was added to about 450 kg of the blockcopolymer solution after filtration, the reactor was purged withnitrogen and the solution was stirred at 30° C. for one hour. Thereaction solution was sampled, and after confirming that the solutionwas neutral, the reaction was terminated. Then, the reactor waspressurized to 0.1 to 0.4 MPaG with nitrogen, and a solid was separatedusing a pressure filtering machine (filtration area of 0.45 m²) equippedwith polyester felt as a filtration material to obtain the polymersolution. 730 g of Irganox 1010 (available from Chiba SpecialtyChemicals Co., Ltd.) was added to the obtained polymer solution anddissolved.

Successively, the solvent component was evaporated from the polymersolution. SCP 100 (heat transfer area: 1 m²) made by Kurimoto Ltd. wasused as an evaporator. The evaporation of the polymer solution wascarried out by setting a heat transfer oil at the inlet of theevaporator at 180° C., the vacuum degree of the evaporator as 90 Torr,the rotational number of a screw as 60 rpm and the feed speed of thepolymer solution as 32 kg/h. The polymer was made as strand with a diceof 4 mmφ through a discharger, it was cooled with a water vessel filledwith 3% suspension solution of ALFLOW H50ES (main component:ethylenebisstearic acid amide available from NOF Corporation), andcolumnar pellets were obtained by a pelletizer. Thus, pellets of theprecursor 3 of the objective acrylic block copolymer were obtained.

<Reaction Forming Acid Anhydride of Precursor 3>

1 part by weight of hydrotalcite DHT-4A-2 (available from KYOWA ChemicalIndustry Co., Ltd.) as an acid trapping agent was compounded to 100parts by weight of the precursor 3 obtained in the above description,and extrusion-kneaded by setting the rotational number at 150 rpm, thecylinder temperature of a hopper setting portion at 100° C. and allother setting temperature at 260° C. using a biaxial extruder equippedwith a vent (44 mm, L/D=42.25) (made by Japan Steel Works Ltd.) toobtain an objective acrylic block copolymer containing an acid anhydridegroup and a carboxyl group (hereinafter, the polymer obtained isdescribed as “the polymer 3”). At extrusion, the vent orifice wasblocked. Further, at this time, an underwater cut pelletizer (CLS-6-8.1COMPACT LAB SYSTEM, made by GALA INDUSTRIES INC.) was connected with theedge of the biaxial extruder and spherical pellets without an adherencepreventive property were obtained by adding ALFLOW H-50ES (availablefrom NOF Corporation) as an adhesion prevention agent in the circulationwater of the underwater cut pelletizer.

The measurement of conversion efficiency to the acid anhydride group andthe carboxyl group at a t-butyl ester site was carried out byquantifying the amount of isobutylene generated from the t-butyl groupby a thermal decomposition reaction at 280° C. As a result of themeasurement, the conversion efficiency of the obtained resin was atleast 95%.

Preparation Example 4 Synthesis of(MMA-co-BA)-b-(BA-co-TBA)-b-(MMA-co-BA) Type Acrylic Block Copolymer(Hereinafter, Described as “the Precursor 4”)

The following operations were carried out in order to obtain the polymer4.

After a 15 L pressure resistant reactor was purged with nitrogen, 5.74 g(40 mmol) of copper bromide, 674 g (5.3 mol) of BA and 30 g (0.23 mol)of TBA were charged to start stirring. Then, a solution in which 8.0 g(22 mmol) of diethyl 2,5-dibromoadipate as an initiator was dissolved in61.7 g of acetonitrile (treated with nitrogen bubbling) was chargedthereto, and the solution was stirred for 30 minutes while raising atemperature to 75° C. When the inner temperature reached 75° C., 0.69 g(4 mmol) of pentamethyldiethylenetriamine as a ligand was added toinitiate the polymerization of an acrylic polymer block. Apolymerization speed was controlled by addingpentamethyldiethylenetriamine as needed. About 0.2 mL of apolymerization solution as for sampling was extracted from thepolymerization solution periodically from the start of polymerization,and the conversions of BA and TBA were determined by the gaschromatogram analysis of the sampling solution. The polymerization speedwas controlled by adding pentamethyldiethylenetriamine at thepolymerization as needed. Pentamethyldiethylenetriamine was added 3times in total (2.07 g in total) during the polymerization of theacrylic polymer block.

When the conversion of BA reached 94.9% and the conversion of TBAreached 95.7%, 409 g (4.1 mol) of MMA, 77 g (0.6 mol) of BA, 3.96 g (40mmol) of copper chloride, 0.69 g (4 mmol) ofpentamethyldiethylenetriamine and 906 g of toluene (treated withnitrogen bubbling) were added thereto to start the polymerization of themethacrylic polymer block.

The conversions of MMA and BA were determined in the same manner as atthe polymerization of the acrylic polymer block. Sampling was carriedout at charging MMA and BA and the conversions of MMA and BA weredetermined using this as a basis. After charging MMA and BA, the innertemperature was set at 85° C. The polymerization speed was controlled byadding pentamethyldiethylenetriamine at polymerization as needed.Pentamethyldiethylenetriamine was added 4 times in total (2.76 g intotal) during the polymerization of the methacrylic polymer block. Whenthe conversion of MMA was 90.4% and the conversion of BA was 62.0%, 2400g of toluene was added, and the reactor was cooled with a water bath toterminate the reaction.

Toluene was added to the obtained polymerization solution, and it wasdiluted so that the concentration of the polymer was 25% by weight. 16.0g of p-toluene sulfonic acid monohydrate was added to the solution to bestirred for 3 hours at a room temperature, and a precipitated solid wasremoved by filtration.

24.0 g of an absorbent KYOWARD 500SH (available from KYOWA ChemicalIndustry Co., Ltd.) was added to the obtained polymer solution, and themixture was further stirred at a room temperature for one hour. Theabsorbent was filtered by a Kiriyama funnel to obtain a colorlesstransparent polymer solution. The solution was dried and the solvent andthe residual monomer were removed to obtain the precursor 4 of theobjective acrylic block copolymer.

When the GPC analysis of the obtained precursor 4 of the acrylic blockcopolymer was carried out, the number average molecular weight Mn was67,078 and the molecular weight distribution Mw/Mn was 1.38.

<Reaction Forming Acid Anhydride of Precursor 4>

45 g of the precursor 4 obtained in the above description and 0.135 g ofIrganox 1010 (available from Chiba Specialty Chemicals Co., Ltd.) and0.45 g of hydrotalcite DHT-4A-2 (available from KYOWA Chemical IndustryCo., Ltd.) as an acid trapping agent were melt-kneaded at 100 rpm for 20minutes using a LABO Plasto Mill 50C150 (blade shape: roller type R60,made by TOYO SEIKI KOGYO Co., Ltd.) set at 240° C. to obtain an acrylicblock copolymer containing an acid anhydride group and a carboxyl group(hereinafter, the obtained polymer is described as “the polymer 4”).

The measurement of conversion efficiency to the acid anhydride group andthe carboxyl group at a t-butyl ester site was carried out byquantifying the amount of isobutylene generated from the t-butyl groupby a thermal decomposition reaction at by 280° C. As a result of themeasurement, the conversion efficiency of the obtained resin was atleast 95%.

Preparation Example 5 Synthesis of(MMA-co-BA)-b-(BA-co-MEA-co-TBA)-b-(MMA-co-BA) Type Acrylic BlockCopolymer (Hereinafter, Described as “the Precursor 5”)

The following operations were carried out in order to obtain theprecursor 5.

After a 15 L pressure resistant reactor was purged with nitrogen, 7.89 g(55 mmol) of copper bromide, 719 g (5.6 mol) of BA, 146 g (1.1 mol) ofMEA and 81 g (0.63 mol) of TBA were charged to start stirring. Then, asolution in which 11.0 g (31 mmol) of diethyl 2,5-dibromoadipate as aninitiator was dissolved in 81.6 g of acetonitrile (treated with nitrogenbubbling) was charged thereto and the solution was stirred for 30minutes while raising a temperature to 75° C. When the inner temperaturereached 75° C., 0.95 g (5 mmol) of pentamethyldiethylenetriamine as aligand was added to initiate the polymerization of an acrylic polymerblock. The polymerization speed was controlled by addingpentamethyldiethylenetriamine as needed. About 0.2 mL of polymerizationsolution as for sampling was extracted from the polymerization solutionperiodically from the start of polymerization and the conversions of BA,MEA and TBA were determined by the gas chromatogram analysis of thesampling solution. Polymerization speed was controlled by addingpentamethyldiethylenetriamine at polymerization as needed.Pentamethyldiethylenetriamine was added 3 times in total (2.85 g intotal) during the polymerization of the acrylic polymer block.

When the conversion of BA was 97.3%, the conversion of TBA was 97.3% andthe conversion of MEA was 98.0%, 560 g (5.6 mol) of MMA, 132 g (1.0 mol)of BA, 5.44 g (55 mmol) of copper chloride, 0.95 g (5 mmol) ofpentamethyldiethylenetriamine and 1292 g of toluene (treated withnitrogen bubbling) were added thereto to start the polymerization of themethacrylic polymer block.

The conversions of MMA and BA were determined in the same manner as atthe polymerization of the acrylic polymer block. Sampling was carriedout at charging MMA and BA and the conversions of MMA and BA weredetermined using this as a basis. After charging MMA and BA, the innertemperature was set at 85° C. Polymerization speed was controlled byadding pentamethyldiethylenetriamine at polymerization as needed.Pentamethyldiethylenetriamine was added 4 times in total (3.8 g intotal) during the polymerization of the methacrylic polymer block. Whenthe conversion of MMA was 90.0% and the conversion of BA was 60.8%, 2400g of toluene was added and the reactor was cooled with a water bath toterminate the reaction.

Toluene was added to the obtained polymerization solution and it wasdiluted so that the concentration of the polymer was 25% by weight. 20.0g of p-toluene sulfonic acid monohydrate was added to the solution to bestirred for 3 hours at a room temperature, and a precipitated solid wasremoved by filtration.

33 g of an absorbent KYOWARD 500SH (available from KYOWA ChemicalIndustry Co., Ltd.) was added to the obtained polymer solution and themixture was further stirred at a room temperature for one hour. Theabsorbent was filtered by a Kiriyama funnel to obtain a colorlesstransparent polymer solution. The solution was dried and the solvent andthe residual monomer were removed to obtain the precursor 5 of theobjective acrylic block copolymer.

When the GPC analysis of the precursor 5 of the acrylic block copolymerwas carried out, the number average molecular weight Mn was 73,948 andthe molecular weight distribution Mw/Mn was 1.39.

<Reaction Forming Acid Anhydride of Precursor 5>

700 g of the precursor 5 obtained in the above description, 4.2 g ofIrganox 1010 (available from Chiba Specialty Chemicals Co., Ltd.) and7.0 g of hydrotalcite DHT-4A-2 (available from KYOWA Chemical IndustryCo., Ltd.) as an acid trapping agent were melt-kneaded at about 50 rpmfor 50 minutes using a DS1-5MHB-E type kneader (made by MORIYAMA Co.,Ltd.) set at 260° C. to obtain an objective acrylic block copolymercontaining an acid anhydride group and a carboxyl group (hereinafter,the polymer obtained is described as “the polymer 5”).

The measurement of conversion efficiency to the acid anhydride group andthe carboxyl group at a t-butyl ester site was carried out byquantifying the amount of isobutylene generated from the t-butyl groupby a thermal decomposition reaction at by 280° C. As a result of themeasurement, the conversion efficiency of the obtained resin was atleast 95%.

Preparation Example 6 Synthesis of(MMA-co-MEA)-b-(BA-co-TBA)-b-(MMA-co-MEA) Type Acrylic Block Copolymer(Hereinafter, Described as “the precursor 6”)

Following operations were carried out in order to obtain the precursor6. After a 15 L pressure resistant reactor was purged with nitrogen,8.61 g (60 mmol) of copper bromide, 968 g (7.6 mol) of BA and 43 g (0.34mol) of TBA were charged to start stirring. Then, a solution in which12.0 g (33 mmol) of diethyl 2,5-dibromoadipate as an initiator wasdissolved in 88.7 g of acetonitrile (treated with nitrogen bubbling) wascharged, and the inner solution was stirred for 30 minutes while raisinga temperature to 75° C. When the inner temperature reached 75° C., 1.04g (6 mmol) of pentamethyldiethylenetriamine as a ligand was added toinitiate the polymerization of an acrylic polymer block.

About 0.2 mL of polymerization solution as for sampling was extractedfrom the polymerization solution periodically from the start of thepolymerization, and the conversions of BA and TBA were determined by thegas chromatogram analysis of the sampling solution. A polymerizationspeed was controlled by adding pentamethyldiethylenetriamine as needed.Further, pentamethyldiethylenetriamine was added 3 times in total (3.12g in total) during the polymerization of the acrylic polymer block.

When the conversion of BA reached 99.0% and the conversion of TBAreached 98.7%, 637 g (6.4 mol) of MMA, 73 g (0.56 mol) of MEA, 5.94 g(60 mmol) of copper chloride, 1.04 g (6 mmol) ofpentamethyldiethylenetriamine and 1303 g of toluene (treated withnitrogen bubbling) were added thereto to start the polymerization of themethacrylic polymer block.

The conversion of MMA was determined in the same manner as at thepolymerization of the acrylic polymer block. Sampling was carried out atcharging MMA, and the conversion of MMA was determined using this as abasis. After charging MMA, the inner temperature was set at 85° C.Polymerization speed was controlled by addingpentamethyldiethylenetriamine at the polymerization as needed. Further,pentamethyldiethylenetriamine was added 4 times in total (4.16 g intotal) during the polymerization of the methacrylic polymer block. Whenthe conversion of MMA was 94.5%, 2400 g of toluene was added and thereactor was cooled with a water bath to terminate the reaction.

Toluene was added to the obtained reaction solution and it was dilutedso that the concentration of the polymer was 25% by weight. 24.0 g ofp-toluene sulfonic acid monohydrate was added to the solution to bestirred for 3 hours at a room temperature, and a precipitated solid wasremoved by filtration.

34.7 g of an absorbent KYOWARD 500SH (available from KYOWA ChemicalIndustry Co., Ltd.) was added to the obtained polymer solution, and themixture was further stirred at a room temperature for one hour. Theabsorbent was filtered by a Kiriyama funnel to obtain a colorlesstransparent polymer solution. The solution was dried and the solvent andthe residual monomer were removed to obtain the precursor 6 which wasthe objective acrylic block copolymer.

When the GPC analysis of the precursor 6 of the acrylic block copolymerwas carried out, the number average molecular weight Mn was 74,057 andthe molecular weight distribution Mw/Mn was 1.45.

<Reaction Forming Acid Anhydride of Precursor 6>

700 g of the precursor 6 obtained in the above description, 4.2 g ofIrganox 1010 (available from Chiba Specialty Chemicals Co., Ltd.) and7.0 g of hydrotalcite DHT-4A-2 (available from KYOWA Chemical IndustryCo., Ltd.) as an acid trapping agent were melt-kneaded at about 50 rpmfor 50 minutes using a DS1-5MHB-E kneader (made by MORIYAMA Co., Ltd.)set at 260° C. to obtain an objective acrylic block copolymer containingan acid anhydride group and a carboxyl group (hereinafter, the polymerobtained is described as “the polymer 6”).

The measurement of conversion efficiency to the acid anhydride group andthe carboxyl group at a t-butyl ester site was carried out byquantifying the amount of isobutylene generated from the t-butyl groupby a thermal decomposition reaction at by 280° C. As a result of themeasurement, the conversion efficiency of the obtained resin was atleast 95%.

Preparation Example 7 Synthesis of(MMA-co-EA)-b-(BA-co-TBA)-b-(MMA-co-EA) Type Acrylic Block Copolymer(Hereinafter, Described as “the Precursor 7”)

The following operations were carried out in order to obtain theprecursor 7.

A 500 L reactor which was purged with nitrogen was charged with 70.19 kgof n-butyl acrylate, 4.81 kg of t-butyl acrylate and 0.625 kg of cuprousbromide to start stirring. Then, a solution in which 0.872 kg of diethyl2,5-dibromoadipate was dissolved in 6.59 kg of acetonitrile was charged,warm water was flowed into a jacket, and the solution was stirred for 30minutes while raising a temperature of the inner solution to 75° C. Whenthe inner temperature reached 75° C., 75.5 g ofpentamethyldiethylenetriamine was added to initiate the polymerizationof an acrylic polymer block. A polymerization speed was controlled byadding pentamethyldiethylenetriamine at polymerization as needed.Pentamethyldiethylenetriamine was added 3 times in total (226.5 g intotal) during the polymerization of the acrylic polymer block.

When the conversion reached 97.4%, 101.7 kg of toluene, 0.431 kg ofcuprous chloride, 45.54 kg of methyl methacrylate, 9.26 kg of ethylacrylate and 75.5 g of pentamethyldiethylenetriamine were added theretoto start the polymerization of the methacrylic polymer block. When theconversion of methyl methacrylate was 91.1%, 220 kg of toluene was addedto dilute the reaction solution and the reactor was cooled to terminatethe reaction. When the GPC analysis of the obtained block copolymer wascarried out, the number average molecular weight Mn was 73,700 and themolecular weight distribution Mw/Mn was 1.39.

30 kg of toluene was added to the obtained block copolymer solution andthe concentration of the polymer was adjusted to 25% by weight. 1.74 kgof p-toluene sulfonic acid was added to the solution, the reactor waspurged with nitrogen, and the solution was stirred for 3 hours at 30° C.The reaction solution was sampled, and after confirming that thesolution was colorless and transparent, 2.48 kg of RADIOLITE #3000available from Showa Chemical Industry Co., Ltd. was added thereto.Then, the reactor was pressurized to 0.1 to 0.4 MPaG with nitrogen, anda solid was separated using a pressure filtering machine (filtrationarea of 0.45 m²) equipped with polyester felt as a filtration material.

1.86 kg of KYOWARD 500SH was added to about 450 kg of the blockcopolymer solution after filtration, the reactor was purged withnitrogen and the solution was stirred at 30° C. for one hour. Thereaction solution was sampled, and after confirming that the solutionwas neutral, the reaction was terminated. Then, the reactor waspressurized to 0.1 to 0.4 MPaG with nitrogen, and a solid was separatedusing a pressure filtering machine (filtration area of 0.45 m²) equippedwith polyester felt as a filtration material to obtain the polymersolution. 737 g of Irganox 1010 (available from Chiba SpecialtyChemicals Co., Ltd.) was added to the obtained polymer solution, anddissolved.

Successively, the solvent component was evaporated from the polymersolution. SCP 100 (heat transfer area: 1 m²) made by Kurimoto Ltd. wasused as an evaporator. The evaporation of the polymer solution wascarried out by setting heat transfer oil at the inlet of the evaporatorat 180° C., the vacuum degree of the evaporator at 90 Torr, the screwrotational number at 60 rpm and the feed speed of the polymer solutionat 32 kg/h. The polymer was made as strand with a dice with 4 mmφthrough a discharger, it was cooled with a water vessel filled with a 3%suspension solution of ALFLOW H50ES (main component: ethylenebisstearicacid amide available from NOF Corporation), and then, columnar pelletswere obtained by a pelletizer. Thus, pellets of the precursor 7 of theobjective acrylic block copolymer were obtained.

<Reaction Forming Acid Anhydride of Precursor 7>

1 part by weight of hydrotalcite DHT-4A-2 (available from KYOWA ChemicalIndustry Co., Ltd.) as an acid trapping agent was compounded to 100parts by weight of the precursor 7 obtained in the above description,and extrusion-kneaded by setting a rotational number at 150 rpm, thecylinder temperature at a hopper setting portion at 100° C. and allother setting temperatures at 260° C. using a biaxial extruder equippedwith a vent (44 mm, L/D=42.25) (made by Japan Steel Works Ltd.) toobtain an objective acrylic block copolymer containing an acid anhydridegroup and a carboxyl group (hereinafter, the obtained polymer isdescribed as “the polymer 7”). At extrusion, the vent orifice wasblocked. Further, at this time, an underwater cut pelletizer (CLS-6-8.1COMPACT LAB SYSTEM, made by GALA INDUSTRIES INC.) was connected with theedge of the biaxial extruder and spherical pellets without adherencepreventing property were obtained by adding ALFLOW (trade mark) H-50ES(available from NOF Corporation) as an adhesion preventing agent in thecirculation water of the underwater cut pelletizer.

The measurement of conversion efficiency to the acid anhydride group andthe carboxyl group at a t-butyl ester site was carried out byquantifying the amount of isobutylene generated from the t-butyl groupby a thermal decomposition reaction at 280° C. As a result of themeasurement, the conversion efficiency of the obtained resin was atleast 95%.

Preparation Example 8 Synthesis of(MMA-co-EA)-b-(BA-co-TBA)-b-(MMA-co-EA) Type Acrylic Block Copolymer(Hereinafter, Described as “the Precursor 8”)

The following operations were carried out in order to obtaining theprecursor 8.

A 500 L reactor which was purged with nitrogen was charged with 71.83 kgof n-butyl acrylate, 3.23 kg of t-butyl acrylate and 0.804 kg of cuprousbromide to start stirring. Then, a solution in which 1.12 kg of diethyl2,5-dibromoadipate was dissolved in 6.59 kg of acetonitrile was charged,warm water was flowed into a jacket, and the solution was stirred for 30minutes while raising the temperature of the inner solution to 75° C.When the inner temperature reached 75° C., 97.1 g ofpentamethyldiethylenetriamine was added to initiate the polymerizationof an acrylic polymer block. A polymerization speed was controlled byadding pentamethyldiethylenetriamine at polymerization as needed.Pentamethyldiethylenetriamine was added 3 times in total (291.3 g intotal) during the polymerization of the acrylic polymer block.

When the conversion reached 99.1%, 97.6 kg of toluene, 0.555 kg ofcuprous chloride, 45.29 kg of methyl methacrylate, 7.36 kg of ethylacrylate and 97.1 g of pentamethyldiethylenetriamine were added theretoto start the polymerization of the methacrylic polymer block. When theconversion of methyl methacrylate reached 95.8%, 220 kg of toluene wasadded to dilute the reaction solution, and the reactor was cooled toterminate the reaction. When the GPC analysis of the obtained blockcopolymer was carried out, the number average molecular weight Mn was62,400 and the molecular weight distribution Mw/Mn was 1.44.

30 kg of toluene was added to the obtained block copolymer solution, andthe concentration of the polymer was adjusted to 25% by weight. 2.24 kgof p-toluene sulfonic acid was added to the solution, the inside of thereactor was purged with nitrogen, and the solution was stirred for 3hours at 30° C. The reaction solution was sampled, and after confirmingthat the solution was colorless and transparent, 2.48 kg of RADIOLITE#3000 available from Showa Chemical Industry Co., Ltd. was addedthereto. Then, the reactor was pressurized to 0.1 to 0.4 MPaG withnitrogen, and a solid was separated using a pressure filtering machine(filtration area of 0.45 m²) equipped with polyester felt as afiltration material.

2.44 kg of KYOWARD 500SH was added to about 450 kg of the blockcopolymer solution after filtration, the inside of the reactor waspurged with nitrogen, and the solution was stirred at 30° C. for onehour. The reaction solution was sampled, and after confirming that thesolution was neutral, the reaction was terminated. Then, the reactor waspressurized to 0.1 to 0.4 MPaG with nitrogen, and a solid was separatedusing a pressure filtering machine (filtration area of 0.45 m²) equippedwith polyester felt as a filtration material to obtain the polymersolution. 728 g of Irganox 1010 (available from Chiba SpecialtyChemicals Co., Ltd.) was added to obtained the polymer solution anddissolved.

Successively, the solvent component was evaporated from the polymersolution. SCP 100 (heat transfer area: 1 m²) made by Kurimoto Ltd. wasused as an evaporator. The evaporation of the polymer solution wascarried out by setting heat transfer oil at the inlet of the evaporatorat 180° C., the vacuum degree of the evaporator at 90 Torr, the screwrotational number at 60 rpm and the feed speed of the polymer solutionat 32 kg/h. The polymer was made as strand with a dice with 4 mmφthrough a discharger, it was cooled with a water vessel filled with a 3%suspension solution of ALFLOW H50ES (main component: ethylenebisstearicacid amide available from NOF Corporation), and then columnar pelletswere obtained by a pelletizer. Thus, pellets of the precursor 8 of theobjective acrylic block copolymer were obtained.

<Reaction Forming Acid Anhydride of Precursor 8>

1 part by weight of hydrotalcite DHT-4A-2 (available from KYOWA ChemicalIndustry Co., Ltd.) as an acid trapping agent was compounded to 100parts by weight of the precursor 8 obtained in the above description andextrusion-kneaded by setting a rotational number at 150 rpm, thecylinder temperature at a hopper setting portion at 100° C. and allother setting temperatures at 260° C. using a biaxial extruder equippedwith a vent (44 mm, L/D=42.25) (made by Japan Steel Works Ltd.) toobtain an objective acrylic block copolymer containing an acid anhydridegroup and a carboxyl group (hereinafter, the obtained polymer isdescribed as “the polymer 8”). At extrusion, the vent orifice wasblocked. Further, at this time, an underwater cut pelletizer (CLS-6-8.1COMPACT LAB SYSTEM, made by GALA INDUSTRIES INC.) was connected with theedge of the biaxial extruder, and spherical pellets without adhesionpreventing property were obtained by adding ALFLOW (trade mark) H-50ES(available from NOF Corporation) as an adhesion preventing agent in thecirculation water of the underwater cut pelletizer.

The measurement of conversion efficiency to the acid anhydride group andthe carboxyl group at a t-butyl ester site was carried out byquantifying the amount of isobutylene generated from the t-butyl groupby a thermal decomposition reaction at 280° C. As a result of themeasurement, the conversion efficiency of the obtained resin was atleast 95%.

Preparation Example 9 Synthesis of(MMA-co-EA)-b-(BA-co-TBA)-b-(MMA-co-EA) Type Acrylic Block Copolymer(Hereinafter, Described as “the Precursor 9”)

The following operations were carried out in order to obtain theprecursor 9.

A 500 L reactor which was purged with nitrogen was charged with 73.40 kgof n-butyl acrylate, 1.61 kg of t-butyl acrylate and 0.638 kg of cuprousbromide to start stirring. Then, a solution in which 1.12 kg of diethyl2,5-dibromoadipate was dissolved in 6.59 kg of acetonitrile was charged,warm water was flowed into a jacket, and the solution was stirred for 30minutes while raising a temperature of the inner solution to 75° C. Whenthe inner temperature reached 75° C., 77.1 g ofpentamethyldiethylenetriamine was added to initiate the polymerizationof an acrylic polymer block. Polymerization speed was controlled byadding pentamethyldiethylenetriamine at the polymerization as needed.Pentamethyldiethylenetriamine was added 2 times in total (154.2 g intotal) during the polymerization of the acrylic polymer block.

When the conversion reached 99.2%, 97.6 kg of toluene, 0.441 kg ofcuprous chloride, 45.27 kg of methyl methacrylate, 7.36 kg of ethylacrylate and 77.1 g of pentamethyldiethylenetriamine were added theretoto start the polymerization of the methacrylic polymer block. When theconversion of methyl methacrylate reached 95.4%, 220 kg of toluene wasadded to dilute the reaction solution and the reactor was cooled toterminate the reaction. When the GPC analysis of the obtained blockcopolymer was carried out, the number average molecular weight Mn was60,400 and the molecular weight distribution Mw/Mn was 1.49.

30 kg of toluene was added to the block copolymer solution obtained, andthe concentration of the polymer was adjusted to 25% by weight. 2.03 kgof p-toluene sulfonic acid was added to the solution, the inside of thereactor was purged with nitrogen, and the solution was stirred for 3hours at 30° C. The reaction solution was sampled, and after confirmingthat the solution was colorless and transparent, 6.10 kg of RADIOLITE#3000 available from Showa Chemical Industry Co., Ltd. was addedthereto. Then, the reactor was pressurized to 0.1 to 0.4 MPaG withnitrogen, and a solid was separated using a pressure filtering machine(filtration area of 0.45 m²) equipped with polyester felt as afiltration material.

2.44 kg of KYOWARD 500SH was added to about 450 kg of the blockcopolymer solution after filtration, the inside of the reactor waspurged with nitrogen and the solution was stirred at 30° C. for onehour. The reaction solution was sampled, and after confirming that thesolution was neutral, the reaction was terminated. Then, the reactor waspressurized to 0.1 to 0.4 MPaG with nitrogen and a solid was separatedusing a pressure filtering machine (filtration area of 0.45 m²) equippedwith polyester felt as a filtration material to obtain the polymersolution. 728 g of Irganox 1010 (available from Chiba SpecialtyChemicals Co., Ltd.) was added to the obtained polymer solution anddissolved.

Successively, the solvent component was evaporated from the polymersolution. SCP 100 (heat transfer area: 1 m²) made by Kurimoto Ltd. wasused as an evaporator. The evaporation of the polymer solution wascarried out by setting a heat transfer oil at the inlet of theevaporator at 180° C., the vacuum degree of the evaporator at 90 Torr,the screw rotational number at 60 rpm and the feed speed of the polymersolution at 32 kg/h. The polymer was made as strand with a dice with 4mmφ through a discharger, it was cooled with a water vessel filled witha 3% suspension solution of ALFLOW H50ES (main component:ethylenebisstearic acid amide available from NOF Corporation), and then,columnar pellets were obtained by a pelletizer. Thus, pellets of theprecursor 9 of the objective acrylic block copolymer were obtained.

<Reaction Forming Acid Anhydride of Precursor 9>

1 part by weight of hydrotalcite DHT-4A-2 (available from KYOWA ChemicalIndustry Co., Ltd.) as an acid trapping agent was compounded to 100parts by weight of the precursor 9 obtained in the above description andextrusion-kneaded by setting a rotational number at 150 rpm, thecylinder temperature at a hopper setting portion at 100° C. and allother setting temperatures at 260° C. using a biaxial extruder equippedwith a vent (44 mm, L/D=42.25) (made by Japan Steel Works Ltd.) toobtain an objective acrylic block copolymer containing an acid anhydridegroup and a carboxyl group (hereinafter, the obtained polymer isdescribed as “the polymer 9”). At extrusion, the vent orifice wasblocked. Further, at this time, an underwater cut pelletizer (CLS-6-8.1COMPACT LAB SYSTEM, made by GALA INDUSTRIES INC.) was connected with theedge of the biaxial extruder, and spherical pellets without adhesionpreventing property were obtained by adding ALFLOW (trade mark) H-50ES(available from NOF Corporation) as an adhesion preventing agent in thecirculation water of the underwater cut pelletizer.

The measurement of conversion efficiency to the acid anhydride group andthe carboxyl group at a t-butyl ester site was carried out byquantifying the amount of isobutylene generated from the t-butyl groupby a thermal decomposition reaction at 280° C. As a result of themeasurement, the conversion efficiency of the obtained resin was atleast 95%.

Preparation Example 10 Synthesis of (MMA-co-BA)-b-BA-b-(MMA-co-BA) TypeAcrylic Block Copolymer (Hereinafter, Described as the Polymer 10)

The following operations were carried out in order to obtain the polymer10.

After a 5 L separable flask as a polymerization container was purgedwith nitrogen, 5.7 g (40 mmol) of copper bromide was weighed and 59 g ofacetonitrile (treated with nitrogen bubbling) was added thereto. Afterstirring by heating at 70° C. for 30 minutes, 8.0 g (22 mmol) of diethyl2,5-dibromoadipate as an initiator and 671 g (5.2 mol) of BA were addedthereto. The mixture was stirred by heating at 85° C., and 0.69 g (4.0mmol) of pentamethyldiethylenetriamine as a ligand was added to initiatepolymerization.

About 0.2 mL of polymerization solution as for sampling was extractedfrom the polymerization solution periodically from the start ofpolymerization and the conversion of BA was determined by the gaschromatogram analysis of the sampling solution. A polymerization speedwas controlled by adding pentamethyldiethylenetriamine as needed. Whenthe conversion of BA reached 94.5%, 391 g (3.9 mol) of MMA, 61 g (0.47mol) of BA, 4.0 g (40 mmol) of copper chloride, 0.69 g (4.0 mmol) ofpentamethyldiethylenetriamine and 841 g of toluene (treated withnitrogen bubbling) were added thereto. The conversions of MMA and BAwere determined in the same manner. When the conversion of MMA was 90.5%and the conversion of BA was 67.1% based on the concentration of BA justafter the addition of MMA/TBMA/BA, 1500 g of toluene was added theretoand the reactor was cooled with a water bath to terminate the reaction.

The reaction solution was diluted with 700 g of toluene, 16.0 g ofp-toluene sulfonic acid monohydrate was added to be stirred for 3 hoursat a room temperature, and a precipitated solid content was removed byfiltration. 16.0 g of an absorbent KYOWARD 500SH (available from KYOWAChemical Industry Co., Ltd.) was added to the obtained polymer solution,and the mixture was further stirred at a room temperature for one hour.The absorbent was filtered by a Kiriyama funnel to obtain a colorlesstransparent polymer solution. The solution was dried, and the solventand the residual monomer were removed to obtain the objective polymer10.

When the GPC analysis of the obtained polymer 10 was carried out, thenumber average molecular weight Mn was 62600 and the molecular weightdistribution Mw/Mn was 1.44.

Preparation Example 11 Synthesis of (MMA-co-BA)-b-BA-b-(MMA-co-BA) TypeAcrylic Block Copolymer (Hereinafter, Described as the Polymer 11)

The following operations were carried out in order to obtain the polymer11.

After a 5 L separable flask as a polymerization container was purgedwith nitrogen, 11.3 g (78.5 mmol) of copper bromide was weighed and 180ml of acetonitrile (dried with molecular sieves 3A and then treated withnitrogen bubbling) was added thereto. After stirring by heating at 70°C. for 5 minutes, it was cooled to a room temperature again, and 5.7 g(15.7 mmol) of diethyl 2,5-dibromoadipate as an initiator and 804.6 g(900.0 ml) of n-butyl acrylate were added. The mixture was stirred byheating at 80° C., and 1.6 ml (7.9 mmol) ofpentamethyldiethylenetriamine as a ligand was added to initiatepolymerization. About 0.2 ml of a polymerization solution as forsampling was extracted from the polymerization solution periodicallyfrom the start of polymerization and the conversion of butyl acrylatewas determined by the gas chromatogram analysis of the samplingsolution. A polymerization speed was controlled by addingpentamethyldiethylenetriamine as needed. When the conversion of n-butylacrylate reached 95%, 345.7 g (369.3 ml) of methyl methacrylate, 7.8 g(78.5 mmol) of copper chloride, 1.6 ml (7.9 mmol) ofpentamethyldiethylenetriamine and 1107.9 ml of toluene (dried withmolecular sieves 3A and then treated with nitrogen bubbling) were addedthereto. The conversion of methyl methacrylate was determined in thesame manner. When the conversion of methyl methacrylate was 85% and theconversion of n-butyl acrylate was 98%, 1500 ml of toluene was added andthe reactor was cooled with a water bath to terminate the reaction. Thepolymerization solution was always green during the reaction.

The reaction solution was diluted with 4000 ml of toluene, 22.1 g ofp-toluene sulfonic acid monohydrate was added to be stirred at 23° C.for 3 hours. After removing the insoluble portion precipitated byfiltering with a Kiriyama funnel, 9.7 g of an absorbent KYOWARD 500SHwas added to the polymer solution and the mixture was further stirred at23° C. for 3 hours. The absorbent was filtered by a Kiriyama funnel toobtain a colorless transparent polymer solution. The solution was dried,and the solvent and the residual monomer were removed to obtain theobjective polymer 11.

When the GPC analysis of the obtained polymer 11 was carried out, thenumber average molecular weight Mn was 119,200 and the molecular weightdistribution Mw/Mn was 1.51. Further, when compositional analysis by NMRwas carried out, it was BA/MMA=72/28 (% by weight).

Preparation Example 12 Synthesis of (MMA-co-BA)-b-BA-b-(MMA-co-BA) TypeAcrylic Block Copolymer (Hereinafter, Described as “the Polymer 12”)

The following operations were carried out in order to obtain the polymer12.

After a 2 L separable flask as a polymerization container was purgedwith nitrogen, 2.7 g (19 mmol) of copper bromide was weighed and 31 g ofacetonitrile (treated with nitrogen bubbling) was added thereto. Afterstirring by heating at 70° C. for 30 minutes, 2.7 g (7.5 mmol) ofdiethyl 2,5-dibromoadipate as an initiator and 358 g (2.8 mol) of BAwere added. The mixture was stirred by heating at 85° C., and 0.33 g(1.9 mmol) of pentamethyldiethylenetriamine as a ligand was added toinitiate polymerization.

About 0.2 mL of polymerization solution as for sampling was extractedfrom the polymerization solution periodically from the start of thepolymerization, and the conversion of BA was determined by the gaschromatogram analysis of the sampling solution. Polymerization speed wascontrolled by adding pentamethyldiethylenetriamine as needed. When theconversion of BA is 85.5%, 193 g (1.9 mol) of MMA, 1.87 g (19 mmol) ofcopper chloride, 0.33 (1.9 mmol) of pentamethyldiethylenetriamine and349 g of toluene (treated with nitrogen bubbling) were added thereto.The conversions of MMA and BA were determined in the same manner. Whenthe conversion of MMA was 90.6% and the conversion of BA was 94.0%, 600g of toluene was added and the reactor was cooled with a water bath toterminate the reaction.

Toluene was added to the obtained reaction solution and it was dilutedso that the concentration of the polymer was 25% by weight. 7.6 g ofp-toluene sulfonic acid monohydrate was added to the solution to bestirred at a room temperature for 3 hours, and a precipitated solid wasremoved by filtration. 11.0 g of an absorbent KYOWARD 500SH (availablefrom KYOWA Chemical Industry Co., Ltd.) was added to the obtainedpolymer solution and the mixture was further stirred at a roomtemperature for one hour. The absorbent was filtered by a Kiriyamafunnel to obtain a colorless transparent polymer solution. The solutionwas dried and the solvent and the residual monomer were removed toobtain the objective polymer 12.

When the GPC analysis of the obtained polymer 12 was carried out, thenumber average molecular weight Mn was 92,713 and the molecular weightdistribution Mw/Mn was 1.33.

Preparation Example 13 Synthesis of(MMA-co-BA-co-MEA)-b-(BA-co-MEA)-b-(MMA-co-BA-co-MEA) Type Acrylic BlockCopolymer (Hereinafter, Described as “the Polymer 13”)

The following operations were carried out in order to obtain the polymer13.

A 500 L reactor which was purged with nitrogen was charged with 53.7 kgof butyl acrylate, 27.2 kg of 2-methoxyethyl acrylate and 0.649 kg ofcuprous bromide to start stirring. Successively, warm water was flowedinto a jacket, and the temperature of the inner solution was raised to70° C. to be kept for 30 minutes. Then, a solution in which 0.905 kg ofdiethyl 2,5-dibromoadipate was dissolved in 6.82 kg of acetonitrile wascharged, and a temperature was raised to 75° C. When the innertemperature reached 75° C., 94.5 ml of pentamethyldiethylenetriamine wasadded to initiate the polymerization of the first block.

When the conversion reached 95%, 79.1 kg of toluene, 0.448 kg of cuprouschloride, 43.5 kg of methyl methacrylate and 94.5 ml ofpentamethyldiethylenetriamine were added thereto to start thepolymerization of the second block. When the conversion of MMA reached90%, 104 kg of toluene was added to dilute the reaction solution and thereactor was cooled to terminate the reaction. When the GPC analysis ofthe obtained block copolymer was carried out, the number averagemolecular weight Mn was 67,152 and the molecular weight distributionMw/Mn was 1.37.

160 kg of toluene was added to the obtained block copolymer solution,and the concentration of the polymer was adjusted to 25% by weight. 1.29kg of p-toluene sulfonic acid was added to the solution, the inside ofthe reactor was purged with nitrogen, and the solution was stirred for 3hours at 30° C. The reaction solution was sampled, and after confirmingthat the solution was colorless and transparent, 2.39 kg of RADIOLITE#3000 available from Showa Chemical Industry Co., Ltd. was addedthereto. Then, the reactor was pressurized to 0.1 to 0.4 MPaG withnitrogen, and a solid was separated using a pressure filtering machine(filtration area of 0.45 m²) equipped with polyester felt as afiltration material.

1.79 kg of KYOWARD 500SH was added to about 478 kg of the blockcopolymer solution obtained after filtration, the inside of the reactorwas purged with nitrogen, and the solution was stirred at 30° C. for onehour. The reaction solution was sampled, and after confirming that thesolution was neutral, the reaction was terminated. Then, the reactor waspressurized to 0.1 to 0.4 MPaG with nitrogen, and a solid was separatedusing a pressure filtering machine (filtration area of 0.45 m²) equippedwith polyester felt as a filtration material to obtain the polymersolution.

512 g of Irganox 1010 (available from Chiba Specialty Chemicals Co.,Ltd.) was added to the obtained polymer solution and dissolved.

Successively, the solvent component was evaporated from the polymersolution. SCP 100 (heat transfer area: 1 m²) made by Kurimoto Ltd. wasused as an evaporator. The evaporation of the polymer solution wascarried out by setting heat transfer oil at the inlet of the evaporatorat 180° C., the vacuum degree of the evaporator at 90 Torr, the screwrotational number at 60 rpm and the feed speed of the polymer solutionat 32 kg/h. The polymer was made as strand through a dice with 4 mmφ andcolumnar pellets were obtained by a pelletizer after cooling with awater bath (the polymer 13).

Example 1

A proportion of 5 parts by weight of ARUFON XG4010 (available fromTOAGOSEI Co., Ltd.) of an acrylic polymer which was all acryl andcontained at least 1.1 (an approximate value of 4 (from the catalogue))of epoxy groups in a molecule, 0.5 part by weight of carbon black (ASAHI#15; available from Asahi Carbon Co., Ltd.) and 0.3 part by weight ofIrganox 1010 (available from Chiba Specialty Chemicals Co., Ltd.) basedon 100 parts by weight (38 g) of the polymer 1 obtained in PreparationExample 1 was melt-kneaded at 100 rpm for 15 minutes using a LABO PlastoMill 50C150 (blade shape: roller type R60, made by TOYO SEIKI KOGYO Co.,Ltd.) set at 100° C. to obtain a block sample.

The obtained sample was molded at a set temperature of 200° C. for 5minutes with a hot press (a compression molding machine NSF-50 made byShinto Metal Industries Ltd.) using a skin crepe metal plate and moldedarticles for evaluation having a thickness of 1 mm on which the skincrepe pattern was transcribed were obtained. Ethanol resistance, oilresistance, urethane adhesivity and heat resistance test were measuredfor these molded articles. The result is shown in Table 1. Further, thepowder slash property test was carried out for powder obtained bypulverizing the block sample obtained in the above description. Further,an insoluble content ratio (% by weight) was measured by using a powderbefore the powder slash molding and a sheet after molding. The result isshown in Table 1.

Example 2

A proportion of 5 parts by weight of ARUFON XG4010 (available fromTOAGOSEI Co., Ltd.) of an acrylic polymer which was all acryl andcontained at least 1.1 (an approximate value of 4 (from the catalogue))of epoxy groups in a molecule, 20 parts of calcium carbonate (SOFTON3200; available from Bihoku Funka Kogyo Co., Ltd.), 0.5 part by weightof carbon black (ASAHI #15; available from Asahi Carbon Co., Ltd.) and0.3 part by weight of Irganox 1010 (available from Chiba SpecialtyChemicals Co., Ltd.) based on 100 parts by weight (38 g) of the polymer1 obtained in Preparation Example 1 was melt-kneaded at 100 rpm for 15minutes using a LABO Plasto Mill 50C150 (blade shape: roller type R60,made by TOYO SEIKI KOGYO Co., Ltd.) set at 100° C. to obtain a blocksample.

The obtained sample was molded at a set temperature of 200° C. for 5minutes with a hot press (a compression molding machine NSF-50 made byShinto Metal Industries Ltd.) using a skin crepe metal plate and moldedarticles for evaluation having a thickness of 1 mm on which the skincrepe pattern was transcribed were obtained. Ethanol resistance, oilresistance, urethane adhesivity and heat resistance test were measuredfor these molded articles. The result is shown in Table 1. Further, thepowder slash property test was carried out for powder obtained bypulverizing the block sample obtained in the above description. Further,an insoluble content ratio (% by weight) was measured by using a powderbefore the powder slash molding and a sheet after molding. The result isshown in Table 1.

Example 3

The operations in the same manner as Example 1 were carried out exceptthat the compounding parts of XG4010 and SOFTON 3200 of Example 2 werechanged, and a block sample was obtained to be evaluated. The result isshown in Table 1.

Example 4

A proportion of 10 parts by weight of ARUFON XG4010 (available fromTOAGOSEI Co., Ltd.) of an acrylic polymer which was all acryl andcontained at least 1.1 (an approximate value of 4 (from the catalogue))of epoxy groups in a molecule, 43 parts of calcium carbonate (SOFTON3200; available from Bihoku Funka Kogyo Co., Ltd.) and 1.4 parts byweight of carbon black (ASAHI #15; available from Asahi Carbon Co.,Ltd.) based on 100 parts by weight (700 g) of the polymer 2 obtained inPreparation Example 2 was melt-kneaded at about 50 rpm for about 30minutes using a DS1-5MHB-E kneader (made by MORIYAMA Co., Ltd.) set at100° C. to obtain a block sample. At this time, a rotational number wassuitably lowered at a time at which resin temperature was going toexceed 130° C.

The obtained sample was molded at a set temperature of 200° C. for 5minutes with a hot press (a compression molding machine NSF-50 made byShinto Metal Industries Ltd.) using a skin crepe metal plate and moldedarticles for evaluation having a thickness of 1 mm on which the skincrepe pattern was transcribed were obtained. Ethanol resistance, oilresistance, urethane adhesivity, heat resistance test, and weightmarking test were measured for these molded articles. The result isshown in Table 1. Further, the powder slash property test was carriedout for powder obtained by pulverizing the block sample obtained in theabove description. Further, an insoluble content ratio (% by weight) wasmeasured by using a powder before the powder slash molding and a sheetafter molding. The result is shown in Table 1.

Example 5

The operations in the same manner as Example 1 were carried out exceptthat the compounding parts of ARUFON XG4010 (available from TOAGOSEICo., Ltd.) of Example 4 was changed to 5 parts by weight, and a blocksample was obtained to be evaluated. The result is shown in Table 1.

Example 6

The operations in the same manner as Example 4 were carried out exceptthat the polymer 2 of Example 4 was changed to the polymer 3 ofPreparation Example 3, and a block sample was obtained to be evaluated.The result is shown in Table 1.

Example 7

The operations in the same manner as Example 4 were carried out exceptthat the polymer 2 of Example 4 was changed to the polymer 4 ofPreparation Example 4, and a block sample was obtained to be evaluated.The result is shown in Table 1.

Example 8

The operations in the same manner as Example 4 were carried out exceptthat the polymer 2 of Example 4 was changed to the polymer 5 ofPreparation Example 5, and a block sample was obtained to be evaluated.The result is shown in Table 1.

Example 9

A proportion of 10 parts by weight of ARUFON XG4010 (available fromTOAGOSEI Co., Ltd.) of an acrylic polymer which was all acryl andcontained at least 1.1 (an approximate value of 4 (from the catalogue))of epoxy groups in a molecule, 43 parts of calcium carbonate (SOFTON3200; available from Bihoku Funka Kogyo Co., Ltd.) and 1.4 parts byweight of carbon black (ASAHI #15; available from Asahi Carbon Co.,Ltd.) based on 100 parts by weight (700 g) of the polymer 6 obtained inPreparation Example 6 was melt-kneaded at about 50 rpm for about 30minutes using a DS1-5MHB-E kneader (made by MORIYAMA Co., Ltd.) set at100° C. to obtain a block sample. At this time, a rotational number wassuitably lowered at a time at which resin temperature was going toexceed 130° C.

The obtained sample was molded at a set temperature of 200° C. for 5minutes with a hot press (a compression molding machine NSF-50 made byShinto Metal Industries Ltd.) using a skin crepe metal plate and moldedarticles for evaluation having a thickness of 1 mm on which the skincrepe pattern was transcribed were obtained. Scratch test was carriedout on these molded articles. The result is shown in Table 1. Further,the powder slash property test was carried out for powder obtained bypulverizing the block sample obtained in the above description. Ethanolresistance, oil resistance, urethane adhesivity and heat resistance testwere measured for the sheet obtained in the powder slash property test.The result is shown in Table 1.

Example 10

A proportion of 10 parts by weight of ARUFON XG4010 (available fromTOAGOSEI Co., Ltd.) of an acrylic polymer, 43 parts of calcium carbonate(SOFTON 3200; available from Bihoku Funka Kogyo Co., Ltd.) and 1.4 partsby weight of carbon black (ASAHI #15; available from Asahi Carbon Co.,Ltd.) based on 100 parts by weight of the polymer 7 obtained inPreparation Example 7 was extrusion-kneaded at a rotational number of100 rpm and all cylinder temperature of 80° C. using a biaxial extruderequipped with a vent LABOTEX30HSS (made by Japan Steel Works Ltd.) toobtain a pellet sample.

The obtained sample was molded at a set temperature of 200° C. for 5minutes with a hot press (a compression molding machine NSF-50 made byShinto Metal Industries Ltd.) using a skin crepe metal plate and moldedarticles for evaluation having a thickness of 1 mm on which the skincrepe pattern was transcribed were obtained. Scratch test was carriedout on these molded articles. The result is shown in Table 1. Further,the powder slash property test was carried out for powder obtained bypulverizing the block sample obtained in the above description. Ethanolresistance, oil resistance, urethane adhesivity and heat resistance testwere measured for the sheet obtained in the powder slash property test.The result is shown in Table 1.

Example 11

The operations in the same manner as Example 10 were carried out exceptthat the polymer 7 of Example 10 was changed to the polymer 8, and apellet sample and a molded article were obtained and the evaluation wascarried out in the same manner for these. The result is shown in Table1.

Example 12

Operation in the same manner as Example 10 was carried out except thatthe polymer 7 of Example 10 was changed to the polymer 9, and a pelletsample and a molded article were obtained and evaluation was similarlycarried out for these. The result is shown in Table 1.

Comparative Example 1

A proportion of 0.5 part by weight of carbon black (ASAHI #15; availablefrom Asahi Carbon Co., Ltd.) and 0.3 part by weight of Irganox 1010(available from Chiba Specialty Chemicals Co., Ltd.) based on 100 partsby weight (38 g) of the polymer 10 obtained in Preparation Example 10was melt-kneaded at 100 rpm for 15 minutes using a LABO Plasto Mill5OC150 (blade shape: roller type R60, made by TOYO SEIKI KOGYO Co.,Ltd.) set at 190° C. to obtain a block sample.

The obtained sample was molded at a set temperature of 200° C. for 5minutes with a hot press (a compression molding machine NSF-50 made byShinto Metal Industries Ltd.) using a skin crepe metal plate and moldedarticles for evaluation having a thickness of 1 mm on which the skincrepe pattern was transcribed were obtained. Ethanol resistance, oilresistance, urethane adhesivity and heat resistance test were measuredfor these molded articles. The result is shown in Table 1. Further, thepowder slash property test was carried out for the powder obtained bypulverizing the block sample obtained in the above description. Theresult is shown in Table 2. Further, an insoluble content ratio (% byweight) was measured by using a powder before the powder slash moldingand a sheet after molding. It is clear that powder slash moldability isexcellent, but heat resistance is inferior.

Comparative Example 2

43 Parts of calcium carbonate (SOFTON 3200; available from Bihoku FunkaKogyo Co., Ltd.), 1.4 parts by weight of carbon black (ASAHI #15;available from Asahi Carbon Co., Ltd.) and 0.6 part by weight of Irganox1010 (available from Chiba Specialty Chemicals Co., Ltd.) based on 100parts by weight of the polymer pellet 10 obtained in Preparation Example10 were compounded, the mixture was discharged as strand at a screwrotational number of 100 rpm and a cylinder temperature of 80° C. usinga biaxial extruder equipped with a vent LABOTEX30HSS (made by JapanSteel Works Ltd.), and successively, columnar pellets were formed by apelletizer.

The obtained sample was molded at a set temperature of 200° C. for 5minutes with a hot press (a compression molding machine NSF-50 made byShinto Metal Industries Ltd.) using a skin crepe metal plate and moldedarticles for evaluation having a thickness of 1 mm on which the skincrepe pattern was transcribed were obtained. Ethanol resistance, oilresistance, urethane adhesivity, heat resistance test, and weightmarking test were measured for these molded articles. The result isshown in Table 1. Further, the powder slash property test was carriedout for powder obtained by pulverizing the pellet obtained in the abovedescription. The result is shown in Table 2. It is clear that the powderis excellent in the powder slash moldability but the molded article isinferior in heat resistance and strain restorability.

Comparative Example 3

The operations in the same manner as Comparative Example 1 were carriedout except that the polymer 11 was used in place of the polymer 10 ofComparative Example 1, and a block sample was obtained to be evaluated.The result is shown in Table 2. It is clear that the molded article isexcellent in heat resistance but the powder is inferior in powder slashmoldability.

Comparative Example 4

The operations in the same manner as Comparative Example 2 were carriedout except that the polymer 11 of Preparation Example 11 was used inplace of the polymer 10 of Comparative Example 2, and pellets and amolded article were obtained to be evaluated in the same manner. Theresult is shown in Table 2. It is grasped that the molded article isexcellent in heat resistance but the powder is inferior in powder slashmoldability.

Comparative Example 5

The operations in the same manner as Comparative Example 2 were carriedout except that the polymer 12 of Preparation Example 12 was used inplace of the polymer 10 of Comparative Example 2, and pellets and amolded article were obtained to be evaluated in the same manner. Theresult is shown in Table 2. It is clear that the molded article isexcellent in heat resistance but the powder is inferior in powder slashmoldability.

Comparative Example 6

Operation in the same manner as Comparative Example 2 was carried outexcept that the polymer 13 of Preparation Example 13 was used in placeof the polymer 10 of Comparative Example 2, and pellets and a moldedarticle were obtained to be similarly evaluated. The result is shown inTable 2. It is grasped that the powder is superior in powder slashmoldability and the molded article is inferior in heat resistance.

TABLE 1 Ex. 1 2 3 4 5 6 7 8 9 10 11 12 Polymer 1 100 100 100 Polymer 2100 100 Polymer 3 100 Polymer 4 100 Polymer 5 100 Polymer 6 100 Polymer7 100 Polymer 8 100 Polymer 9 100 XG4010 5 5 10 10 5 10 10 10 10 10 1010 SOFTON 3200 20 40 40 40 40 40 40 43 43 43 43 ASAHI #15 0.5 0.5 0.50.5 0.5 0.5 0.5 0.5 1.4 1.4 1.4 1.4 Ethanol resistance ◯ ◯ ◯ ◯ ◯ ◯ ◯ Δ ◯◯ ◯ ◯ Oil resistance ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ Heat resistance ◯ ◯ ◯ ◯ ◯ ◯◯ ◯ ◯ ◯ ◯ ◯ Urethane adhesion property ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ Powderslash property ◯ ◯ ◯ Δ Δ Δ ◯ ◯ ◯ ◯ ◯ ◯ Insoluble content ratio 0 0 0 — —— — — — — — — before molding (% by weight) Insoluble content ratio 66 7391 — — — — — — — — — after molding (% by weight)

TABLE 2 Com. Ex. 1 2 3 4 5 6 Polymer 10 100 100 Polymer 11 100 100Polymer 12 100 Polymer 13 100 XG4010 SOFTON 3200 40 40 40 40 ASAHI #150.5 0.5 0.5 0.5 0.5 0.5 Ethanol resistance ◯ ◯ ◯ ◯ ◯ Δ Oil resistance ◯◯ ◯ ◯ ◯ ◯ Heat resistance X X ◯ ◯ ◯ X Urethane adhesion property Δ Δ Δ ΔΔ Δ Powder slash property ◯ ◯ X X X ◯ Insoluble content ratio before 0 00 0 0 0 molding (% by weight) Insoluble content ratio after 0 0 0 0 0 0molding (% by weight)

As cleared from Table 1 (Examples 1 to 12) and Table 2 (ComparativeExamples 1 to 6), it is clear that the thermoplastic elastomercomposition of the present invention is excellent in powder slashmoldability, and additionally, improves the heat resistance of themolded article obtained by a crosslinking reaction (the increase ofinsoluble content ratio) in comparison with only a block copolymer.Further, it is clear that it is also excellent in ethanol resistance andoil resistance. Further, when the obtained sheet is used as asuperficial skin material for an automobile, it is required to adherewith polyurethane generally used as a substrate, but it is clear thatthe sheet is favorably adhered.

INDUSTRIAL APPLICABILITY

Since the molded article obtained by molding the thermoplastic elastomercomposition of the present invention is excellent in heat resistance,weather resistance, chemical resistance, adhesivity, flexibility,abrasion resistance, it can be used as materials having purposes such asa superficial material, a touch material, an appearance material, anabrasive resistant material, an oil resistant material, a dumpingmaterial and an adherent material; as arbitrary shapes such as a sheet,a flat panel, a film, a small size molded article, a large size moldedarticle and the other shapes; further, as parts such as panels,steerings, grips and switches; and further as a sealing material. Theiruses are not particularly limited, but uses for an automobile, for homeelectronics products or for electric products for office supplies areexemplified. Examples thereof are a superficial skin material for anautomobile, a touch material for an automobile, an appearance materialfor an automobile, panels for an automobile, steerings for anautomobile, grips for an automobile, switches for an automobile andpanels for electric products at home or office, switches for electricproducts at home or office. Among those, it is preferably used for asuperficial skin for an automobile interior.

1. A molded article, comprising an acrylic block copolymer (A) whichcomprises a methacrylic polymer block (a) and an acrylic polymer block(b), wherein at least one of polymer blocks among the methacrylicpolymer block (a) and the acrylic polymer block (b) has an acidanhydride group and/or a carboxyl group, and an acrylic polymer (B)having 1.1 or more of epoxy groups in one molecule, wherein the acidanhydride group and/or the carboxyl group is reacted with the epoxygroup at molding, and the acrylic block copolymer (A) is crosslinked. 2.The molded article of claim 1, wherein the acid anhydride group and/orthe carboxyl group exist in the main chain of the acrylic blockcopolymer (A) and the acid anhydride group is represented by the generalformula (1):

(wherein R′ is hydrogen or a methyl group and may be the same ordifferent, n is an integer of 0 to 3 and m is an integer of 0 or 1). 3.The molded article of claims 1 or 2, wherein the acrylic block copolymer(A) comprises 10 to 60% by weight of the methacrylic polymer block (a)in which a methacrylic polymer is the main component and 90 to 40% byweight of the acrylic polymer block (b) in which an acrylic polymer isthe main component.
 4. The molded article of claim 1, wherein theacrylic polymer block (b) comprises 50 to 100% by weight of at least onemonomer selected from the group consisting of n-butyl acrylate, ethylacrylate and 2-methoxyethyl acrylate and 50 to 0% by weight of otheracrylate ester and/or other vinyl monomer copolymerizable with thesemonomers.
 5. The molded article of claim 1, wherein the number averagemolecular weight measured by gel permeation chromatography of theacrylic block copolymer (A) is 30,000 to 200,000.
 6. The molded articleof claim 1, wherein a ratio (Mw/Mn) of the weight average molecularweight (Mw) to the number average molecular weight (Mn) measured by gelpermeation chromatography of the acrylic block copolymer (A) is 1.8 orless.
 7. The molded article of claim 1, wherein the acrylic blockcopolymer (A) is a block copolymer produced by atom transfer radicalpolymerization.
 8. The molded article of claim 1, wherein the glasstransition temperature of the methacrylic polymer block (a) is 25 to130° C.
 9. The molded article of claim 1, wherein the weight averagemolecular weight of the acrylic polymer (B) is 30,000 or less.
 10. Themolded article of claim 1, wherein a glass transition temperature of theacrylic polymer (B) is at most 100° C.
 11. The molded article of claim1, wherein the acrylic polymer (B) comprises 50 to 100% by weight of atleast one monomer selected from the group consisting of n-butylacrylate, ethyl acrylate and 2-methoxyethyl acrylate and 50 to 0% byweight of other acrylate ester and/or other vinyl monomercopolymerizable with these monomers.
 12. The molded article of claim 1,wherein the weight average molecular weight of the acrylic polymer (B)is 500 to 10,000.
 13. The molded article of claim 1, wherein 5 to 200parts by weight of a filler is further added based on 100 parts byweight of the acrylic block copolymer.
 14. The molded article of claim1, wherein 0.1 to 20 parts by weight of a lubricant is further addedbased on 100 parts by weight of the acrylic block copolymer.
 15. Themolded article of claim 1, which is obtained by powder slush molding.16. A superficial skin for an automobile interior, which comprises themolded article of claim 1.